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The collective positioning and behaviours of elite netball players are an important concept to understand, as they relate to the tactical plans and overall performance of a team. However, this is currently an under-researched field in most indoor team sports owning to previous limitations in indoor tracking systems. Thus, this thesis investigated the use of collective tactical variables in elite netball matches and training, captured using a local positioning system (LPS). Collective tactical variables were used to explore collective movement and positioning behaviours in matches, examining the more successful movement patterns and how these varied in small sided games (SSGs), commonly used in training. Study 1 assessed the validity of the Catapult T6 LPS to measure inter-unit distance. Eight recreationally-active, female indoor team-sport players completed a circuit comprised of seven movements (walk, jog, jump, sprint, 45º change of direction and shuffle), on an indoor court. Participants wore a receiver tag (ClearSky T6, Catapult Sports) and seven reflective markers, allowing for comparison with the reference system (©Vicon Motion Systems, Oxford Metrics, UK). The criterion validity against the reference system resulted in a root mean square error of 0.20 ± 0.05 m. Additionally, analysis was conducted on five distance bands to assess the association between distance and inter-unit distance validity. The resulting mean bias presented an overestimation for the LPS in all distance bands, while the percentage of variance accounted for remained stable for all distance bands, excluding the > 20 m band. These results suggest the Catapult T6 LPS has acceptable accuracy - within 20 cm - for measuring inter-unit distance, as such opening up opportunities for further research into collective tactical variables for indoor team sports. Study 2 of this thesis used the validated ClearSky LPS to explore collective tactical variables during seven elite netball matches at the team and sub-group level. Collective tactical variables were explored during attacking and defending possessions and included; inter-player distance, width, length, surface area, centroids, width-per-length ratio and stretch indices. During attack, the team and all sub-groups adopted greater lateral dispersion between players, while on defence there was generally greater longitudinal dispersion. Additionally, greater irregularity (measure of predictability within time-series data) was observed in sub-groups most present and active in the play (forwards on attack, defenders on defence). Study 3 followed on from the results of the previous study, by modelling the effects of collective tactical variables and contextual predictors on scoring probability in elite netball. The effects were estimated via a logistic-regression version of the generalized linear mixed model, with adjustments for several predictor variables. Extremely short possessions were associated with decreased scoring probability, while lateral dispersion negatively affected the probability of scoring for both teams. These results indicated that, in general, it is more favourable to maintain positioning and ball movement in the middle of the court. Finally, Study 4 focused on SSGs, which are commonly used in training to replicate match outputs. The collective tactical variables of four attacking and four defending elite netball players were analysed to compare three SSG conditions: 4v4, 5v5 and 6v6. Two, 20-min SSGs for each condition were analysed using a linear mixed model. The irregularity of width-per-length ratio of the four attacking and four defending players was greatest in 4v4, the attackers’ inter-player distance and length variability was greatest in 5v5, while the four attacking players had the smallest mean surface area in 6v6. This thesis provides an exploration into the use of collective tactical variables in elite netball. As a combination of studies, this thesis is an important investigation into methods available for performance analysis research in netball and other indoor team sports. The key findings showing tactical analysis via collective tactical behaviours hold useful information for elite netball. Of interest, different patterns of positioning and movements exist between attacking and defending phases of play and sub-groups. All sub-groups displayed increases to their lateral dispersion during attack and active sub-groups presented greater irregularity, aligning with the positional dependencies and restrictions of netball. Also, certain collective tactical variable outputs are more successful than others, most prominent being shorter possession associated with decreased score probability, suggesting maintaining ball possession early is a key driver in score probability. Finally, in training SSGs differ tactically with different number of players included in the drills, with lower numbers causing defenders to exhibit greater irregularity while for greater numbers, players were closer to their teammates, both results displaying specific coaching principles that can be trained.

Previous research has found mental imagery (MI) to be an effective tool for enhancing performance and skill learning across a range of contexts from sport to music and dance. The beneficial effects of MI are often contextualised through the functional equivalence hypothesis, which proposes that MI and physical practice (PP) activate similar neural mechanisms. Therefore, MI research has often emphasised replicating critical aspects of PP in MI to maximise functional equivalence. Despite this, the MI research literature has rarely investigated the application of key skill acquisition principles commonly utilised in PP to MI. One approach to skill acquisition strongly influencing our current understanding of how to develop skill is nonlinear pedagogy (NLP). NLP draws on key principles of ecological dynamics, proposing that skill development is nonlinear, and emerges as the result of dynamic learner-environment interactions. Captured this way, implementation of NLP design principles such as constraint manipulation, representative design, information- movement coupling, and movement variability are proposed to facilitate the development of adaptable, individualised movement solutions. Given the emphasis on creating MI practice conditions that mimic PP, using a NLP informed approach in MI may help facilitate the effective development of adaptable, individualised skills that can deal with changing performance contexts. The inclusion of non-sport related skills (e.g., finger tapping) and other psychological techniques in previous MI reviews made it difficult to ascertain how MI directly attributes to skill development in sport. Therefore, Study 1 attempted to address this gap in the literature through a meta-analytic review of MI, focusing on sport-specific-motor skills. From the 36 studies reviewed, it was found that MI has a significant positive effect on the development of sport-specific-motor skills (g = 0.476). Further analysis revealed MI combined with PP to be most effective (g = 0.579). Skill complexity, MI delivery type (i.e., MI combined or independent of PP), and performance measures were found to moderate the efficacy of MI interventions. A key finding that has helped to further understanding about the impact of MI interventions was the identification of skill complexity as moderating MI effectiveness. Results indicated that MI interventions practicing simple skills are significantly more effective relative to more demanding, complex movements. However, MI research investigating complex sport-specific-motor skills was lacking (5/58 analysed effect sizes). The need for further MI research on complex sport-specific-motor skills formed the rationale for selecting the power clean (PC) – a complex Olympic weightlifting skill – in Study 4 of this thesis. An ecological dynamics perspective of skill acquisition in PP was presented in Study 2, highlighting the importance of adaptability in skill development and the relevance of such a perspective to MI was discussed. The applicability of NLP design principles to MI interventions was presented alongside practical examples of how these principles could be integrated alongside existing MI guidelines. Key considerations included the incorporation of movement variability through task constraint manipulation, inclusion of critical aspects of performance environment (e.g., defensive pressure and other team members), and the use of movement outcome focused instructions. This study provided the theoretical foundation to further examine the application of NLP to MI interventions. Based on the review of NLP research in Chapter 2, the influence of a NLP approach for skills that emphasise movement form for performance (e.g., Olympic weightlifting) was identified as an area for further investigation. Specifically, preliminary case study evidence was identified using a constraints-based approach (key methodological influence on NLP) to the PC (e.g., Verhoeff et al., 2018) which presented promising results for the use of ecological dynamics informed approaches (i.e., NLP). Therefore, the effectiveness of NLP relative to linear pedagogy (LP) practice was investigated in Study 3. This study involved beginner learners to engage in either NLP or LP practice of the PC over a 4-week intervention. Contrary to predictions, exploratory behaviour (i.e., presence of movement variability) was not significantly different between NLP and LP conditions. However, equivalent improvements between conditions in performance accuracy (i.e., FxD; forward barbell displacement) were observed. This suggested that pedagogical approach may not be a precondition for adopting a particular technique, and inherent individual and task constraints may require learners to self-organise behaviour to develop an individual task solution. Importantly, deviation from an instructed technical model does not appear to lead to less efficient performance. Such a finding has important implications for a practitioner’s overall learning philosophy. Even in activities considered to rely upon a specific movement form (i.e., PC), practitioners might want to distinguish between techniques that are effective and movement patterns that look correct. That is, the effectiveness of the movement for producing specific outcomes may be more a more important consideration than reproducing the ideal ‘aesthetic’ or movement style (i.e., what the movement looks like). Study 4 aimed to investigate the influence of a NLP approach to MI in relation to a LP practice approach to MI with beginners learning the PC. The same design was implemented as Study 3 (i.e., practice sessions, instructions, reps, and 3-D motion capture and horizontal barbell displacement). Like Study 3, no significant differences were observed in exploratory behaviour and equivalent improvements in performance accuracy (RxD; rearward barbell displacement) for both conditions. Consistent with the Study 3, these findings suggest that establishing a movement pattern that achieves overall performance goals (e.g., reduced forward or backward barbell displacement) is more important than replicating a prescribed technique that looks correct. Considered with the results of Study 3 these results suggest an equivalence in training-related improvements, highlighting that it may be possible to reproduce similar behavioural adaptations observed (to a lesser magnitude) when using NLP or LP approaches in MI. In summary, the aim of this thesis was to enhance our understanding of applying a NLP approach to MI intervention design. Therefore, this thesis did not aim to investigate whether NLP was ‘better’, but rather to provide preliminary findings and hopefully stimulate further discussion about incorporating established skill acquisition principles from PP into MI. It is not definitive whether NLP provides further benefits to skill development over and above LP practice, however, the overall improvement in performance outcomes in Studies 3 and 4 suggest it is a legitimate consideration for future interventions. The lack of significant differences between LP and NLP conditions suggests that despite being prescribed a specific movement form, learners may search for more individually appropriate techniques, and importantly, these deviations are not necessarily detrimental to overall performance.

A high expectation exists from managers in the sport management (SM) industry sector for graduates from undergraduate (UG) SM programs to have extensive practical experience and employability. It is unclear however, from the literature reviewed, of the contribution practical experience plays to graduate employability. Also unclear is how SM employers recognise employable graduates. The purpose of this Australian-based research was to determine how practical experience can align the learning, development, and subsequent capacity of graduates from UG SM programs, to transparently signal their employability during job recruitment and selection. This purpose was refined into three research questions with specific foci. The first research question focused on differentiating and defining SM job classifications to identify broad SM role functions. Associated with these role functions are the skills, attributes, and corresponding knowledge that UGs should develop while undertaking practical experiences in an UG SM program. The focus of the second research question was to examine how learning and development gained from practical experience can transparently be converted into employability signals and observed by prospective SM employers during job recruitment and selection. The third research question focused on providing recommendations to managers from the SM industry sector and coordinators of UG SM programs to assist both sectors prepare UGs to be employable graduates. A mixed methods approach was adopted in three stages. In Stage One a job advertisement audit was conducted of 200 graduate-entry SM positions that stipulated a tertiary qualification and practical experience as prerequisites. The data were analysed through text coding and using descriptive statistics. In Stage Two, semi-structured interviews were conducted with 10 sport managers identified from the job audit. The interview transcripts were coded and thematically analysed. Stage Three involved the conduct of an online employability survey which incorporated eight Employability Dimensions (Rosenberg et al., 2012) with corresponding items, garnering responses from 165 sport managers. However, following data cleansing, 92 responses were analysed using non-parametric statistics.

Tennis coaches’ technical knowledge plays a critical part in performance analysis as it impacts their recommendations to athletes. To date, the research on tennis coaches’ knowledge is limited, and no previous studies have attempted to examine expert tennis coaches’ knowledge and diagnostic ability of the tennis serve technique. This research aimed to examine the knowledge and diagnostic ability of expert and novice tennis coaches, and to identify the key distinguishing characteristics between expert and novice tennis coaches. As a result, the key distinguishing characteristics between expert and novice tennis coaches were identified, and there was a recognised need to develop an online training course to improve coaches’ knowledge and understanding of the tennis serve technique. An online coach education course was then developed, and the effectiveness of the course was evaluated. This thesis comprised three studies employing a mixed-methods design. Data was collected and analysed by using both qualitative and quantitative methods to gain a deeper understanding of novice and expert tennis coaches’ knowledge, diagnostic skills and learning. The main data collection methods were in-depth interview and an online questionnaire that was constructed specifically for this investigation. Pre- and post-intervention design was used to investigate the efficacy of a training intervention on coaches’ knowledge and their diagnostic ability of the tennis serve technique. A video-based test was developed to measure the effectiveness of the online course. As a result of the first two studies, models representing declarative and practical knowledge of expert and novice tennis coaches were developed. The key distinguishing characteristics between novice and expert coaches were that experts displayed a superior understating of the functionality of the tennis serve technique and an advanced diagnostic ability. Expert coaches were able to see the tennis serve as “a whole” in comparison with novices who focused more on separate technical elements. It was suggested that novice coaches need to develop the knowledge of tennis serve from two perspectives: technical and functional. The findings of this thesis extend our current understanding of tennis coaches’ knowledge and diagnostic skills. The development and evaluation of an online training course provides a unique contribution to coach education in order to understand the cause-and-effect relationships between technical elements withing the flat serve should allow tennis coaches to prescribe more effective training interventions. By knowing how one element may affect another, coaches will be able to identify and rectify technical issues by addressing the cause of the problem instead of focusing on many separate elements. The design of this program can also be used with other technical elements in tennis and can be applied to other sports to improve coaches’ knowledge and diagnostic ability of sport technique.

Polycystic Ovary Syndrome (PCOS) is primarily thought of as a reproductive condition, although it has profound effects on metabolic health, with 38-80% of women with PCOS presenting with insulin resistance. This underlying insulin resistance occurs independently of obesity and has negative effects on other features of the condition. The identification of peripheral insulin resistance in PCOS occurred in 1989, and despite several advances in this area, the molecular mechanisms responsible for peripheral insulin resistance in women with PCOS remain unclear. In addition, interventional studies from women with PCOS have identified impaired responses to insulin-sensitizing therapies. A possible explanation for the underlying insulin resistance and poor response to insulin-sensitizing treatments may be the dysregulation of Transforming Growth Factor-beta (TGF-beta) signalling. The dysregulation of TGF-beta signalling is responsible for remodelling in the ovarian tissues and reproductive dysfunction. Due to the systemic action of TGF-beta signalling, it may be conceivable that these effects extend beyond the reproductive tissues to the peripheral tissues. This presents a possible mechanism that could contribute to the development of insulin resistance in women with PCOS. Understanding the underlying mechanisms of insulin resistance will allow for improvements in diagnosis and for targeted therapies to be developed, which are currently lacking for women with PCOS. The overall aim of this thesis was to determine if dysregulated TGF-beta signalling plays a role in skeletal muscle insulin resistance and can influence metabolic responses to exercise in women with PCOS. This was achieved through a combination of in vivo and in vitro studies focusing on skeletal muscle metabolism. Study 1 explored the role of TGF-beta ligands, TGF-beta 1 and Anti-müllerian hormone (AMH), on glucose uptake and insulin signalling in myotubes from women with PCOS and healthy controls. In line with previous studies, we showed that in vivo metabolic phenotype was not accurately retained in cultured myotubes from women with PCOS, suggesting that a combination of the in vivo environmental factors and intrinsic defects lead to the development of insulin resistance. TGF-beta 1 and AMH had distinct metabolic effects. TGF-beta 1 increased basal and insulin-stimulated glucose uptake, while AMH decreased glucose uptake and PI3K-p110 expression, which was accompanied by an increase in inhibitory IRS-1ser312 phosphorylation. Study 2 assessed the response of myotubes from women with PCOS and healthy controls to an in vitro model of contraction with and without TGF-beta 1 or AMH. It was found that myotubes from women with PCOS and healthy controls display minimal differences in exercise-induced signalling transduction. Myotubes from healthy women showed an increase in the phosphorylation of p38 MAPK and CREB, which appeared to be absent in the myotubes from women with PCOS. The TGF-beta ligands AMH and TGF-beta 1 do not appear to influence in vitro skeletal muscle exercise-like signalling responses. In Study 3, a cross-sectional approach was used to assess skeletal muscle TGF-beta and insulin signalling in women with PCOS compared to overweight and lean controls. Insulin sensitivity, as determined by euglycemic–hyperinsulinemic clamp, confirmed previous findings that women with PCOS have a significant reduction in insulin sensitivity compared to controls. This insulin resistance occurred in the absence of any identifiable defects in skeletal muscle insulin signalling and did not appear to be related to TGF-beta signalling. Women with PCOS had greater levels of basal phosphorylation of p38 MAPK, suggesting that excessive reactive oxygen species and/or inflammation may contribute to insulin resistance. In Study 4, overweight women with PCOS participated in a 12-week exercise training intervention. We aimed to determine if changes in insulin sensitivity following 12 weeks of moderate or high-intensity exercise training were related to aberrant TGF-beta signalling and collagen deposition in the skeletal muscle. Exercise training of high and moderate intensities resulted in improvements in insulin sensitivity and cardiorespiratory fitness, with the metabolic benefits being more noticeable following the high-intensity intervention. Improvements in insulin sensitivity occurred independently of changes in body composition, TGF-beta signalling and other clinical measures. Collectively, the results from these studies demonstrate the role of TGF-beta ligands and signalling dysregulation in skeletal muscle metabolism in vitro. However, these findings do not appear to translate in vivo where insulin sensitivity was not related to TGF-beta signalling in women with or without PCOS. There was no apparent evidence of dysregulation of TGF- beta signalling or insulin signalling in women with PCOS. Furthermore, improvements in insulin sensitivity following 12 weeks of high- or moderate-intensity exercise training occurred independently of changes in TGF-beta signalling.

Exercise training provides health benefits to the general population, but there is considerable variability in the individual response to similar training. Some people have limited improvements following exercise (“low responders”), while others seem to improve considerably (“high responders”). To date, most exercise studies that have claimed to identify “low” or “high” responders assumed that if the participants were to repeat the same exercise training, they would show a similar response. However, within- subject variability has not been tested, which might lead to inaccurate classification of exercise responses at the individual level and the waste of precious research resources. Exposing individuals to a repeated or longer training intervention can assist in identifying the magnitude of responses to exercise training with better accuracy. Recent evidence also suggests that the response to exercise training may be influenced by epigenetic signatures. Epigenetics is a reversible process that affects how genes are expressed in cells, and it carries the memory of past cellular and environmental events. To date, no study has tested whether individual response is influenced by epigenetic marks. Thus, the overarching aim of this thesis is to identify the physiological, molecular, and epigenetic marks of exercise responses. Twenty young, healthy men from the Gene SMART (Skeletal Muscle Adaptive Response to Training) study completed a repeated and a longer exercise training intervention to measure within-subject variability and to obtain individual progress curves (See Figure 3.1 for study design). Participants underwent a four-week control period followed by four weeks of High-Intensity Interval Training (HIIT), had a washout period of > 1 year, and underwent another four weeks of HIIT followed by an additional 8 weeks of HIIT. The HIIT program was adjusted to individual fitness levels that were re-assessed every four weeks during the intervention to ensure improvements. Participants’ peak power output (Wpeak), lactate threshold (LT), and maximal oxygen uptake (VO2max) were assessed in duplicates at each time point. We used five known statistical methods to investigate changes in fitness and mixed models to estimate individual response. Muscle biopsies were collected at each time point to measure mitochondrial markers (i.e. mitochondrial respiration, citrate synthase, cytochrome C oxidase, succinate dehydrogenase, mitochondrial copy number, fibre typing, and myosin heavy chains PCRs), as well as genome-wide DNA methylation profiles in skeletal muscle using the Illumina HumanMethylation EPIC array. In Chapter 3, we show that at the group level, all physiological measures increased in a dose-response manner following HIIT (p 0.7 p < 0.001), the TEM was large (7.9 to 27 pmol·s-1·mg-1), and the CV was > 15% for all complexes. We performed statistical simulations to determine the sample size that would be required to detect a range of effect sizes at 80% power. We found that duplicate measurements on 75 participants are required to detect a 6% change in mitochondrial respiration after an intervention. Finally, Chapter 5 and 6 focus on the DNA methylation measures at the group and individual level respectively. For the first time at the group level, we have investigated DNA methylation patterns that are associated with fitness by combining three measurements of performance into a comprehensive z-score (Chapter 5). We found 12,107 DMPs that were associated with baseline fitness (z-score) (FDR < 0.005), 18.2% of which were hypomethylated and 81.8% hypermethylated with higher fitness levels. We identified 1,268 DMRs for baseline fitness, 15.3% of which hypomethylated and 85.7% hypermethylated. Hyper-DMRs were robustly over-represented in genic enhancers and flanking active TSS, and highly depleted in strong and weak candidate enhancers. Hypo and Hyper-DMRs had a moderate association with bivalent enhancers and promoters. Both hyper and hypo-DMRs presented a moderate representation in regions actively repressed by PolyComb proteins. Finally, significant DMRs were enriched for 26 GO terms, and these pathways were related to muscle system processes, actin cytoskeleton organization and regulation of actin filament and cytoskeleton processes. Next, we investigated the effects of exercise on the methylome, and surprisingly we observed an inverse pattern of DNA methylation profile after exercise. In summary, we found 568 DMPs that significantly changed after the 4 weeks (FDR < 0.005), and out of those only 1.4% were hypermethylated and 98.6% were hypomethylated. We identified 17 DMRs associated with changes in DNA methylation in response of 4 weeks of HIIT, and 100% of DMRs were hypomethylated. Lastly, we intersected DMPs that were significant for both baseline fitness z-score and after 4 weeks of HIIT. Five DMPs were significant, and they appeared to have inverse patterns for baseline z-score (more hypermethylation) and 4 weeks of HIIT (more hypomethylation). When we transitioned to the individual level study in Chapter 6, neither of our approaches (i.e. repeated intervention and repeated testing) yielded many significant results: only one DMP was significant (cg11260483, p-value: 3.22000e-10, adj.p-value: 0.00022) after the repeated intervention, and no DMPs significant after the repeated testing approach. The challenging experimental design of this thesis provided high resolution, longitudinal physiological and molecular profiles in skeletal muscle following repeated exercise training and testing. It yielded novel insights into the phenomenon of trainability in humans; young, healthy men displayed individual responses to HIIT at the physiological level, but not at the molecular level. This thesis also issued methodological considerations for protocols aimed at measuring individual response (Chapter 3). In particular, the high within-subject variability we observed led us to conclude that many repeated testings on the same individual at regular intervals during the training program, along with a moderate-to-large sample size, were necessary to estimate inter-individual variability in response to training. The mitochondrial respiration technique showed high technical variability (Chapter 4), making the measurement unreliable in our study with only n = 20 men and only two duplicates per individual. The typical sample sizes used in exercise training studies (n < 20) are likely insufficient to capture exercise-induced changes in mitochondrial respiration at the group level, let alone the individual level. Lastly, we observed a clear DNA methylation profile association with fitness levels (Chapter 5). However, when an exercise intervention was applied, we noticed a change in DNA methylation patterns that were inverse to those observed at baseline for the fitter participants. Such observations left us wondering on potential reasons to why this occurs. Thus, future research should also integrate the methylome with transcriptome and proteome to elucidate the mechanisms underlying adaptations to exercise training.

A key objective of sports performance research is to provide team managers, coaches, and athletes seeking to improve performance with information on the attributes that contribute to or predict overall success, yet the determinants of performance in actual competition remain an under-examined and under-theorised field. The focus of this thesis is an exploration of these determinants, particularly in the more complex races that permit opponent interaction. The rationale and theoretical framework for the thesis is outlined in Chapter 1, where I explain how it is underpinned by concepts from ecological dynamics, utilising a sequential explanatory mixed-methods research approach, first to quantify the changes in cyclist performance in increasingly complex racing environments, followed by a qualitative investigation to explain and elaborate on the potential mechanisms underpinning these changes. In the initial quantitative analyses (Chapters 2 and 3), linear mixed modelling of race results was used to examine changes in the variability and predictability of elite track cyclists' performances between solo time trials and race events involving direct interaction with competitors. In Chapter 2, cyclists’ performances in the three solo time-trials and three mass-start race events that comprise the overall Omnium competition were investigated. The reproducibility of performance in the mass-start events was lower than in the solo events. In Chapter 3, Match Sprint tournaments provided performance measures in a qualifying time trial and subsequent head-to-head racing. Qualifying time-trial performance largely determined success in head-to-head racing, but there was evidence of unknown factors modifying cyclists’ chances of success. In Chapter 4, a systematic narrative review was undertaken, in which published findings on the determinants of cyclists’ behaviours and chances of success in elite competition were collated and synthesised. Key findings were grouped and used to shape a conceptual framework of the determinants of performance. A qualitative research approach was adopted for Chapters 5 and 6, wherein semi-structured interviews with 15 elite cyclists from three racing disciplines were used to explore potential factors underpinning the results in Chapters 2, 3 and 4. Transcribed text of the interviews was examined using thematic inductive content analysis to develop initial themes, which were cross-validated with results from Chapter 4. Chapter 5 focused on the changes in the perceptions and practices of cyclists between solo time trials and race events with direct interaction between opponents. In Chapter 6, other themes of the thematic content analysis are combined with results from each prior study to propose an initial systems model of elite cycling performance, summarising the dimensions, features and mechanisms identified throughout this thesis. Final concluding statements, including the practical applications, limitations and possible future directions of this work are made in Chapter 7. In this thesis, I have demonstrated the advantages of combining research techniques and drawing on research across a range of scientific disciplines in order to enrich our understanding of competitive performance in some cycling disciplines. Research on competitive performance in other sports characterised by complex environments could benefit from this mixed-methods approach.

Many skills underpin the performance of sporting officials, however decision-making is regarded as the most critical. There are finite on-field opportunities to develop decision-making of sporting officials in training and competition, as a consequence, video-based approaches are typically used to assess and develop decision-making skill. Existing methods such as the use of match broadcast video may not be an ecologically valid method to present decision-making scenarios. With technological advancements, using virtual reality may improve the ecological validity of video-based approaches to improve decision-making. Study 1 systematically reviewed existing research utilising video-based testing to assess decision-making in officials, which often differentiates between skill levels to demonstrate construct validity. Study 1 identified several limitations including common use of match broadcast video, limited reporting of reliability, and studies often solely reporting number of decisions rather than performance accuracy. Comparison between video-based and in-game decision-making performance was rarely conducted. This study provided the foundation to further examine the efficacy of video- based tests in sporting officials. Study 2 developed two valid and reliable video-based tests, based on the recommendations of Study 1. As match broadcast video is the most common video-based testing method for officials, it was compared with 360° VR to assess decision-making accuracy. Both 360° VR and match broadcast video-based tests demonstrated construct validity and high reliability (r = 0.89). Stronger ecological validity was evident in 360° VR than match broadcast, as participants rated 360° VR to be more representative of in-game decision-making processes. Study 3 aimed to determine the relationship between decision-making accuracy in both video-based tests (360° VR and match broadcast) and in-game of elite Australian football umpires, given that this limitation of the research was identified in Study 1. Study 3 used validated video-based tests from Study 2. There were no significant relationships observed for decision-making accuracy between in-game and video-based testing. Studies 2 and 3 provide findings on testing, however it is unclear whether 360° VR or match broadcast is more effective for developing decision-making. Study 4 assessed the effectiveness of a video-based training program using 360° VR or match broadcast to develop decision-making in amateur Australian football umpires using a randomised control study design. Decision-making was assessed using the valid and reliable tests of Study 2 before, immediately following, and one month following training (retention test). The 360° VR group exhibited significantly higher decision-making accuracy (p < 0.05) than the control group at retention testing, with no between-group differences observed for the match broadcast group. Participants rated 360° VR as more relevant and enjoyable than match broadcast. In summary, this thesis aimed to develop and evaluate the effectiveness of 360° VR as a video-based testing and training tool in Australian football umpires. Although 360° VR and match broadcast appear to have strong construct validity and reliability, currently, there is limited transfer to in-game performance. Further, based on these results, it is not definitive whether 360° VR is a more effective training tool than match broadcast. The findings of this thesis indicate 360° VR may be more ecologically valid than match broadcast and warrants further investigation.

In Australian football, effective kicking is a critical technical skill to maintain ball possession and more importantly, score. Despite the importance of kicking in Australian football, for talent identification purposes, no assessment of technical match play kicking performance has been developed with sufficient validity. This thesis used notational analysis of match play kicking actions to guide the development of a valid and reliable Australian football field-based kicking assessment and an Australian football small-sided game kicking assessment. These two new field-based assessments contribute to the current array of technical skill assessments to help provide a more sequential skill Performance Assessment Model. The first study (Bonney, Berry, Ball, & Larkin, 2019; Chapter three of this thesis) reviewed current Australian football technical skill assessments using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement as a guideline. A structured framework for practitioners was developed to consider when assessing, or developing, assessments of technical game based skill. The study proposed a 5-Level Performance Assessment Model for athlete assessment. The model applied match play notational analysis to separate technical game skill on a continuum comprising of Level- 1 (i.e., laboratory test), Level-2 (i.e., static field-based test), Level-3 (i.e., dynamic field- based test), Level-4 (i.e., small-sided game field-based test) and Level-5 (i.e., match play). These levels incorporated a step-wise progression of performance demands to more closely represent match-play conditions. The proposed model was suggested to provide researchers and practitioners with a better understanding of the potential technical performance demands and key outcomes associated with each level of the performance model. Study two (Bonney, Berry, Ball, & Larkin, 2020; Chapter four of this thesis) developed a valid and reliable Australian football kicking proficiency assessment comparative to match play kicking performance. Youth male Australian football players (n = 251) from different stages within the Australian football talent pathway were assessed for kicking proficiency and physical performance outcomes. The developed Australian football field-based – dynamic kicking assessment considered particular constraints of match play kicking demands such as the distance of the kick; the speed and running direction of the player kicking the ball; the speed and direction of the player receiving the ball and the type of kick being executed. Content, logical and construct validity and test re-test reliability were assessed. Findings suggested the kicking assessment could distinguish across and between the under 14, under 16 and under 18 age groups (U14; U16; U18) and club, sub-elite and elite skill groups. Kicking proficiency increased from U14 to U18 and as skill level increased from novice to elite. The timeframe between U14 and U16 had the greatest increase in kicking motor pattern development and was identified as a potential key period where kicking skill acquisition may be most impressionable; however, further research was recommended to support this. The developed Australian football field-based – dynamic kicking assessment was the first Australian football specific kicking assessment to consider and apply match play kicking constraints to make a more representative, valid and reliable assessment. Furthermore, this dynamic field-based assessment provides an example of a Level-3 assessment from the Performance Assessment Model where kicking proficiency can be evaluated from a more representative performance environment. The fourth level, of the Performance Assessment Model, required the implementation of a field-based small-sided game assessment. With numerous small- sided game conditions available and limited small-sided game research conducted in Australian football, it was important to investigate how different player number conditions may influence skill involvements and physical responses in Australian football players. Study three (Bonney, Berry, Ball, & Larkin, 2020; Chapter five of this thesis) contributed to this gap in the literature by investigating the effect of four different small- sided game player number conditions (5v5, 5v6, 6v6, 7v7), played in the same 50m zone, on the technical (kicking) and physical (distance travelled total and per minute, maximum velocity and percentage of high intensity running) performance outcomes in 22 sub-elite youth Australian football players. Player number configurations were chosen in consultation with elite U18 Australian football coaches and by considering match play starting configurations (i.e., 6v6 in the forward 50m zone) and then manipulating player numbers around this. Particular constraints were applied to the small-sided game to ensure the focus was on kicking (i.e., after each handball a kick must be performed). The results demonstrated when more technical events are required under more pressure situations (i.e., physical and time) the 5v6 condition appeared to be most appropriate. However, when the focus was on kicking to a contested possession balanced player numbers would appear optimal. Alternatively, when the small-sided game focus was on increasing physical demands lower player density conditions appeared more suitable. These findings were considered with an expert panel of coaches, retired elite players, sub- elite junior players and sport scientists. It was decided the technical and physical performance outcomes in the 5v6 small-sided game were the most appropriate to investigate further in study four. Study four (Bonney, Berry, Ball, & Larkin, 2020; Chapter six of this thesis) developed a valid and reliable 5v6 Australian football small-sided game kicking proficiency assessment. Youth male Australian football players (n = 145) from different stages within the Australian football talent pathway were assessed for technical and physical performance outcomes. Logical validity was determined from player, coach and skill acquisition expert opinion. Construct validity was determined by conducting a one- way analysis of variance to compare between age and skill groups and within an age group. Test re-test and inter-rater reliability were also assessed. Findings suggested the Australian football small-sided kicking assessment was a valid and reliable Australian football kicking proficiency assessment tool, providing an appropriate technical assessment for Level-4 on the Performance Assessment Model. The assessment considered and applied match play kicking constraints to make a more representative assessment of match play demands. The Australian football small-sided kicking assessment was 97% successful in identifying players as either novice or sub-elite. These findings may provide worthwhile information to coaches regarding kicking performance along the Australian Football League pathway, to profile player strengths whilst identifying specific areas of improvement. With the results of study four suggesting the 5v6 Australian football field-based small-sided game was a valid and reliable assessment tool, it was important to investigate the extent to which the small-sided game compared to match play performance. The final study (Bonney, Ball, Berry, & Larkin, 2020; Chapter seven of this thesis) investigated sixteen youth Australian football players to see if the technical and physical match performance outcomes could be replicated in a 5v6 small-sided game. Players were assessed in the small-sided game and then two days later were assessed during match play. Both the testing session and match play analysis occurred at the same ground. The results suggested kicking proficiency, the number of kicks executed, meters travelled per minute and percentage of high intensity running were all higher in the small-sided game than during match play. During match play, players had less time affordance to execute a kick and achieved higher maximum running velocities than during the small-sided game. These findings provided further insights to Australian football youth coaches about the technical and physical performance outcomes of the 5v6 Australian football small-sided game kicking assessment and the technical and physical performance outcomes of match play in youth Australian football players. Understanding these responses could enable Australian football youth coaches to apply more representative training programmes. Overall, results suggest the 5-Level Performance Assessment Model could provide sport coaches with greater clarification of the benefits and limitations of the technical assessment tasks they are using. When players are assessed from a holistic approach the tracking of player development and the display of player strengths and limitations may become more meaningful to coaches and recruiters. Furthermore, the results of studies two, three, four and five provide coaches with alternative options for technical Australian football kicking assessment and training methods. The results from studies two and four indicate that kicking proficiency improves from U13 to U16 and then appears to stabilize; however, as skill level increases so too does kicking proficiency. The greatest percentage of improvement was between U14 and U16 suggesting this may be a key developmental period where kicking skill is more susceptible to development. These results may assist coaches in developing specific technical skill programmes for particular age groups.

The overall aim of this research was to examine the factors that influence the coach-biomechanist relationship in the elite sprinting context and gain an understanding of the factors that impede and enhance performance environments and relationships. It is thought that the transfer of sport science research into coaching practice is not as efficient as it should be, as it has been established that coaches are not using sport science as a source of knowledge. Subsequently, this insufficient transfer of knowledge could be limiting potential improvements in athlete performance. Technique analysis is a common area of expertise for both sprint coaches and biomechanists in high-performance sport and was therefore the ideal context to explore the coach-biomechanist relationship in detail. The first phase of research examined the coach and biomechanists’ understandings of optimal sprint running technique and determined the relationships between the experiential knowledge of the two groups. Findings showed elements that are crucial to optimal sprinting technique, such as the position of the contact foot and extension of the leg during stance. Differences in knowledge between the two groups were complimentary. For example, the biomechanists’ focus on the transition from swing into stance phases and the coaches’ interest in upper body movement. Moreover, the communication of these knowledge differences was potentially problematic. The second phase of this research determined if the knowledge differences found in the first phase influenced the visual search patterns of coaches and biomechanists. This difference was not observed, with visual search behaviour not reflecting the differences in knowledge seen in phase one. The third phase aimed to establish the context in which coaches and biomechanists interact to improve performance. This phase supported previous phases’ results in that communication styles and knowledge differences were impeding factors and added lack of role clarity to this list. The fourth and final phase investigated the interactions and exchange of information that occurs during the technique assessment process. Results showed that the process is a coach-led partnership where rapport building, and equal sharing of knowledge are emphasised. In summary, this research contributes to the understanding of the coach-sport science relationship by providing practical evidence for numerous concepts in a novel and more specialized population. It increases our understanding of coach technical knowledge and visual perceptual behaviour as well as uniquely incorporating the sport biomechanists’ knowledge and perspective into these investigations. The multi-layered approach used allowed the knowledge, behaviours and interactions that comprise qualitative analysis of technique to be investigated. This has greatly improved our understanding of the coach- biomechanist relationship and the factors that impede and enhance it.

There is growing consensus about the importance of physical activity and regular engagement is known to have a number of health and developmental benefits. Accordingly, research across a variety of fields has argued for the importance of laying the foundations for lifelong physical activity engagement in the early years. The school plays a central role in this effort by impacting children’s initial relationships with physical culture. Within the school, PE is often the primary vehicle for the promotion of physical activity. However, the problems with PE and its failure to connect with all children has been widely reported. Concurrently, there has been a significant physical activity dropout rate in adolescence for girls, and some boys. Scholarly attempts to address these concerns have focused mainly on late primary or high school settings, specifically curriculum and pedagogy. To date, very little research has focused on the early (Year One/Two) years of PE, when many children are developing their initial physical subjectivities. Rather than a period which all children enter as a ‘blank slate’, early PE is defined by the differing levels of experience that children bring to class. How these differing levels of embodied experiences are valued mean the children are constantly engaging in a range of stratified interactions. The outcomes of these interactions can have a profound impact on how students engage in physical activity, both in PE and on the playground. To examine how children are embodying and developing their physical subjectivities in these two spaces, a six- month ethnographic project was conducted at a primary school in Victoria. This allowed for the examination of the experiences of a Year 1/2 cohort through the implementation a variety of ethnographic and child-centred methods. Drawing on a theoretical approach, combining Bourdieu (1998) and Collins (2004), this thesis shows how the outcomes of PE activities, impacted the types of activities that children chose to engage in on the playground. Additionally, the findings show how the children play a key role in reproducing the dominant elements of the field (including the ‘naturalized’ gender order inherent in sport/PE) and the hierarchies that contextualized each activity. This research offers an in-depth focus into the complex social processes, in the playground and PE, which continue to usher children along seemingly pre-determined physical paths. This thesis concludes with a call for a critical approach to early PE that incorporates the different experiences of the children to create 2 curricula, with a particular focus on teaching children to be reflective of the impact of their embodied experiences. This also incorporates changes to the playground as a continuation of the PE space.

This thesis involves a study of adolescent participation in gymnasium based exercise programs (GBEPs) in Australia. It investigates the problematic nature of, and the influences on their low levels of participation. Special attention is given to the significance of gymnasiums as spaces for adolescent exercise participation, and—in the light of both the prevailing regulatory context and operations of the Exercise and Fitness Industry (EFI)—the capacity of gymnasium businesses and their workers to appropriately cater for this cohort. The study used a triangulated mixed-method research design, with data sourced from semi-structured telephone interviews, a structured online questionnaire, and documents relating to the operations and conduct of the EFI in Australia. Interviews were conducted with 16 informants, including a government minister, government and industry association executives, and senior managers from gymnasium businesses. Also from across Australia, were 44 parents and/or guardians of adolescent children who completed the questionnaire. The document analysis incorporated independent industry reports and government regulations relevant to the EFI and the context of this study. In particular, industry codes in four state and self-governing mainland territories, which were the main and generally enforceable regulations specific to the EFI in Australia, were examined. The study was framed by stakeholder theory, with the data situated in an analytical setting guided by regulation theory. The findings suggested that gymnasium businesses generally discriminated against adolescents through informal exclusion and restrictive policies on gymnasium based exercise program (GBEP) participation, and it was clear that this customer segment was not given the attention it deserved. In addition, most stakeholders believed that there was a need for better educated and suitably qualified gymnasium instructors and personal trainers, able to provide appropriate supervision, guidance and exercise instruction. Also demonstrated was strong support for external EFI regulation, including mandatory gymnasium business and instructor accreditation, with interview informants, in the main, believing that it would result in better quality and safer industry practices, offering quality assurance. While the findings showed that gymnasiums were mostly viewed as appropriate spaces for adolescent exercise participation, some stakeholders felt that the prevailing levels of regulation of the EFI, as well as its internal practices, were unable to deliver Australia’s adolescents with equitable access and appropriate levels of support to participate effectively in GBEPs. The findings were used to formulate a number of recommendations—predominantly for the EFI—with special attention to advancing the participation of adolescents in GBEPs across Australia. Accordingly, the thesis culminates in the analysis of policy options and strategic opportunities to increase their participation, whilst ensuring equal gymnasium access. This includes the nationwide introduction of external industry regulation, mandatory gymnasium business and instructor accreditation, and a gymnasium access requirement which provides all adolescents with the opportunity to participate in GBEPs. The ensuing recommendations are to support both adolescent and adult GBEP participants, improve enterprise and industry performance, and potentially contribute to building a healthier and more active Australian population.

While seemingly simple, the underlying exercise prescription to bring about the desired adaptations to exercise training is as complicated as that of any drug. Prescribing the frequency, duration, or volume of training is relatively simple as these factors can be altered by manipulating the number of exercise sessions per week, the duration of each session, or the total work performed in a given time frame (e.g., per week). However, prescribing exercise intensity is more complex and there is controversy regarding the reliability and validity of the many methods used to determine and prescribe intensity. Despite their common use, it is apparent V̇ O2 and HR based exercise prescription has no merit to elicit a homogeneous and explicit homeostatic response. Alternatively, the use of submaximal anchors has been employed and perceived to represent shifts in the metabolic state of the working muscle and represent a demarcating point to define training zones. Whereas, the domains of exercise are independent of these anchors and defined by their distinct homeostatic responses, and offer a valid concept for normalising exercise intensity (Chapter 1; Review 1). Furthermore, the relationship between graded exercise test (GXT) derived anchors and constant work load derived anchors is at this point non sequitur and we discourage using submaximal anchors interchangeably (Chapter 2; Study 1). Mitochondria are organelles found inside skeletal muscle cells and their main role is the production of adenosine triphosphate (ATP) which is necessary for skeletal muscle contractions. The bioenergetics demands associated with aerobic exercise lead to a homeostatic perturbation, activating sensor proteins that initiates gene expression through transcriptional and translational processes leading to the development of mitochondrial proteins. The source of ATP production modulates the homeostatic perturbations that activate the sensor proteins which include: an increase in the redox state of the cell (NAD+/NADH), an increase in ATP turnover (measured via AMP/ATP), increased calcium flux and mechanical stress and these are largely influenced by the source of ATP production. These perturbations act as signals to activate sensor proteins that ultimately modulate transcriptional coactivators associated with mitochondrial biogenesis (Chapter 3; Review 2). Despite the relationship between exercise intensity and mitochondrial biogenesis, submaximal exercise intensity is almost exclusively prescribed relative to maximal oxygen uptake or maximal work rate. The well-established limitation of these methods is the inability to normalise exercise intensity; specifically, to elicit a homogenous homeostatic perturbations. Thus, employing methodology that normalises exercise intensity based on homeostatic perturbations may modulate the activation of signalling kinases and the extent of gene expression (Chapter 4; Study 2).

This thesis is an exploration of the controversial hypothesis that a runner’s foot strike pattern defines the demands on the lower extremity, and hence we expect to observe adaptations to its anatomical, mechanical, and neurological function. First, we review the state of the literature to find that long-distance running seems to have an osteogenic and myogenic effect on the foot; however, studies often do not control for foot strike or footwear worn, leading to circumstantial evidence. We therefore aim to determine structural differences between two groups of runners with an antithetical foot strike pattern (habitual rearfoot versus habitual forefoot strikers). We find groups to have similar foot muscle size and to have similar toe flexor strength. Further, we find the trabecular bone volume to be larger in the first metatarsal bone in forefoot strikers; however, the calcaneus reveals no differences between groups in bone density or trabecular structure. We then explore the function of the ankle, in isolation and in coordination with the knee and hip. It appears that habitual forefoot strikers may have access to a wider physiological range of ankle torque and ankle joint angle. This increased potential may allow forefoot strikers to adapt to different footwear by regulating ankle stiffness depending upon motor task. The inter-joint coupling investigation reveals knee-hip coordination pattern of runners to be the most consistent, while ankle-knee couple was the most variable. Forefoot strikers have more variable coordinative patterns than rearfoot strikers irrespective of the footwear worn. We then asked a neuro-mechanical question: Is the control of running kinematics and kinetics influenced by the foot strike type? Using analysis of persistence in time series and analysis of motor redundancy in human movement, we show that rearfoot strikers employ higher active control over critical variables such as limb posture at initial ground contact and leg stiffness. The results suggest that forefoot strikers achieve control of these parameters through exploitation of the abundant degrees of freedom available in the system. Finally, we conclude the thesis with indications for short-term objectives in-line with the research that begun in this thesis.

Csikszentmihalyi (1975) introduced the flow concept, involving total absorption in the task, confidence, and control, with effortless, automatic movement. Flow has nine dimensions that Stavrou and Zervas (2004) divided into five antecedents (challenge-skill balance, clear goals, unambiguous feedback, total concentration on the task, sense of control) and four concomitant dimensions (action-awareness merging, loss of self-consciousness, time transformation, and autotelic experience). Loss of self-consciousness and time transformation have similarities to phenomena often reported in hypnotic trance states. To examine whether the experience of these phenomena in hypnosis enhanced flow state, I performed three studies. In Study 1, I evaluated whether a hypnotic state facilitates flow and enhances performance via its concomitant dimensions and whether the trancework component of traditional hypnosis (TH), compared with neutral hypnosis (NH), is crucial, with 20 golfers, who performed putting under controlled conditions. In Study 2, I examined the effect of two hypnosis techniques, regression (RE) and future progression (FP) on golf putting performance and flow state with 25 golfers. Both studies had the same structure. I used the Waterloo-Stanford Group C Scale of Hypnotic Susceptibility (WSGC) to match participants into conditions. Golfers performed 56 4m test putts at pre-test and post-test. I measured radial error of each putt and number of putts holed. Then they completed the Flow State Scale-2 (FSS-2) at pre- and post-test. All participants undertook a 60-minute, face-to-face session, then listened to a recording of that session for seven days with different hypnotic suggestions in the RE and FP conditions. In Study 1, two-way mixed-design ANOVA revealed that TH reduced radial error and two dimensions of flow, sense of control and loss of self-consciousness, compared with NH. In Study 2, two-way mixed design ANOVA showed that the effect of FP was significantly larger than the effect of RE in facilitating global flow mainly due to the time transformation dimension, but performance was not enhanced. In Study 3, I investigated the effect of FP on flow and putting performance in competitions. Three male golfers participated in a single-case design (SCD) study, comprising six competition rounds in the Baseline Phase (BP) and six rounds in the Intervention Phase (IP). I recorded number of putts per round, percentage distance error, strokes gained putting, global flow state, and flow dimensions. Visual inspection and split-middle technique analysis of individual graphs indicated improvement in performance and flow of two golfers. I used narrative analysis to examine social validation questionnaire responses. Participants reported superior performance with more confidence and greater concentration after the hypnosis intervention. The findings of these three studies indicate that RE and FP hypnosis can be useful techniques to promote flow and improve performance. Further study is warranted to identify the most effective combination of hypnosis techniques to enhance, global flow state, flow dimensions, and performance.

The proportion of older adults (60+ years) globally, is predicted to more than double between 2017 and 2050. Ageing is often associated with declining health and physical capacity, but has the potential to be a positive experience, often termed Active Ageing or successful ageing. The promotion of Active Ageing within the community, is important, to ensure positive experiences of older adults, and to lessen the burden that older adults have on health and social services. Physical activity (PA) and social support are key determinants of Active Ageing, however, PA declines with age. The aim of this PhD was to investigate Active Ageing in the community, through participation in volunteer-run community activity PA and social programs. This research adopted a case-study approach, specifically the community organisation and associated activities, was Life Activities Clubs Victoria (LACVI). This research included two systematic reviews (study 1), a longitudinal self-report quantitative survey study (n=35, mean age=67) administered in three waves (baseline, six and twelve months) analysed using linear mixed models, and four focus groups (n=24) which were analysed using thematic analysis. A mixed-methods study synthesising results from the survey study and two focus groups (n=11) explored the impact of participation in social and PA programs on social wellbeing, PA and health (study 2a and b). The final qualitative study, analysed the four focus groups, including participants from LACVI and other community activity programs (e.g. Men’s Shed). This study explored how and why participation in PA and social programs impact wellbeing. Study 1. The systematic reviews investigated the association between social support or social integration and PA. In summary, social support for PA and social integration factors, having large friendship networks, and connecting widely and regularly with people, were positively associated with PA levels. Study 2 a and b. Synthesis of the findings of the mixed methods study suggested that program participation significantly reduced loneliness. In addition, participants felt they gained social connectedness through program participation and this was especially important at times of significant life events. The studies suggested that socially oriented PA programs increased motivation to adhere to PA programs long term. This was supported by maintenance of PA levels over one year in the PA groups compared to reduction over one year in social group participants. Study 3. The final qualitative study utilised a leisure-based model of wellbeing to explore the aspects of program participation that older adults felt were important for their wellbeing. in summary, older adults appreciated groups that they could identify with, in order to develop new social contacts, with activities that gave them control, enjoyment, meaning and challenge in their lives. The analysis suggested that both social and PA programs could provide these. Overall, this program of research suggests that community activity programs for older adults offer a variety of benefits for older adults and thereby promote Active Ageing, especially when a variety of types of activity are offered in one setting, with a social focus and in a way that older adults feel they can relate to.

Chronic heart failure (CHF) is characterised by an inability of the heart to pump enough blood to meet the body’s metabolic needs, resulting in exercise intolerance. A reduction in nitric oxide (NO) bioavailability has been implicated as an initiator and/or contributor to many of the peripheral skeletal tissue dysfunctions that contribute to the exercise intolerance in patients with CHF. Inorganic nitrate supplementation has been identified as an important mediator of exercise tolerance via increasing NO bioavailability, but the potential efficacy of this on patients with heart failure with reduced ejection fraction (HFrEF) as well as the effect on vascular function is not well understood and was the focus of Study 1. Additionally, to our knowledge, no previous study has examined the potential impact of nitrate supplementation on cardiac performance during submaximal exercise and mitochondrial respiration in individuals with HFrEF. These were the foci of Studies 2 and 3 respectively. Study 1: The effect of dietary inorganic nitrate supplementation on exercise tolerance and vascular function in patients with HFrEF. The primary aim of this study was to determine the effect of chronic inorganic nitrate supplementation on exercise tolerance, as measured by peak aerobic capacity (VO2peak) and time to exhaustion (TTE), during treadmill exercise in patients with HFrEF. A secondary aim was to determine the effect of chronic supplementation on vascular function (endothelial function) in these patients. Methods: Sixteen patients with HFrEF (15 men and 1 woman, 63 ± 4 y, BMI: 31.8 ±2.1 kg∙m-2) completed the primary outcome of this study (exercise tolerance), and 12 completed the vascular function component. Participants were randomly allocated, in a double-blind, crossover design, to consume either a nitrate rich beetroot juice (16mmol nitrate/day), or a nitrate-depleted placebo for five days prior to the first testing visit. Participants then continued daily dosing until they completed a cardiopulmonary exercise test (CPX) and a battery of vascular function assessments (peripheral and central blood pressure (BP) as well as aortic stiffness and brachial artery flow mediated dilation (BAFMD)). Results: There were significant increases in both plasma nitrate (p0.05) changes in peripheral tissue oxygenation during exercise, as measured non-invasively with near-infrared spectroscopy (NIRS). There were no differences in the brachial blood pressure measurements including systolic blood pressure (SBP) (nitrate: 130 ± 4 mmHg, placebo: 132 ± 5 mmHg, p=0.58), diastolic blood pressure (DBP) (nitrate: 80 ± 3 mmHg, placebo: 81 ± 3 mmHg, p= .74) and mean arterial pressure (MAP) (nitrate: 96 ± 3 mmHg, placebo: 98 ± 4 mmHg, p=0.67). There were also no significant differences in aortic pressure or stiffness. BAFMD reactive hyperaemic percent change tended to improve (nitrate: 5.7% ± 1.1, placebo: 4.1% ± 0.7, (p=0.06), and this change had a moderate effect size (ES) (Cohen’s d 0.607). Conclusions: Results from this study indicate the nitrate appears ineffective at improving exercise tolerance and vascular function in HFrEF. Future studies should explore alternative interventions to improve peripheral muscle tissue function in HFrEF. Study 2: The effect of dietary nitrate supplementation on cardiac output and stroke volume during submaximal exercise in men with HFrEF: a pilot study. The primary aim of this exploratory study was to determine the effect of chronic inorganic nitrate supplementation on cardiac performance during three submaximal exercise bouts. Methods: Five male patients with HFrEF (61 ± 3y) completed this pilot study. Participants consumed either the nitrate-rich beetroot juice (16 mmol nitrate) or the placebo an average of 13 ± 2 days prior to the testing visit. They completed a three-stage (15-25 watts, 25-40 watts and 35-60 watts) discontinuous exercise protocol on an echo-compatible recumbent cycle ergometer with simultaneous Doppler echocardiography. Cardiac output (Q̇) and stroke volume (SV) were derived using the Doppler velocity time integral via the Huntsman method. Results: There were significant increases in both plasma nitrate (p=0.004, ES=3.54) and nitrite (p=0.01, ES=0.82) following nitrate supplementation. Although not statistically significant (all p>0.27), the differences in Q̇during stage two and stage three had medium to large ES (stage two: nitrate: 6.4 ± .4 L∙min-1, placebo: 5.3 ±. 2 L∙min-1, ES=1.51; stage three: nitrate: 7.5 ± 0.6 L∙min-1, placebo: 6.4 ± 0.7 L∙min-1, ES=0.50) exercise. Changes in Q̇ were accompanied by medium to large ES changes in SV (stage two: ES=0.97 and stage three: ES=0.57) and medium to large increases in heart rate (HR) at rest and all exercise stages. These differences were likely mediated by a reduction in total peripheral resistance (TPR) at stage two (ES=-1.62) and stage three (ES=-0.81). Conclusions: We report potentially clinically important improvements in measures of cardiac performance during submaximal exercise following nitrate supplementation in patients with HFrEF. The initial findings from this pilot study warrant further investigation in larger and more diverse samples in order to determine the efficacy of this intervention. Study 3: The effect of dietary nitrate supplementation on mitochondrial respiration in men with HFrEF. The primary aim of this exploratory study was to determine the effect of chronic inorganic nitrate supplementation on parameters of mitochondrial respiration in patients with HFrEF. Methods: Seven male participants (62 ± 2y) completed this invasive study. Participants consumed the nitrate rich beetroot juice (16mmol nitrate/day) or a placebo for an average of 15 ± 2 days prior to their muscle biopsy. Muscle samples were taken from the vastus lateralis. Mitochondrial respiration was assessed using high resolution respirometry. Western blot analysis was used to assess the protein content of mechanistic target of rapamycin complex 1 (mTORC1), p38 mitogen activated protein kinase (p38MAPK), protein kinase B (Akt), and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α). Results: Plasma nitrate increased (831%, p0.05). Similarly, there were no differences in mitochondrial content, as assessed by citrate synthase activity (p=0.73) and no differences were noted in total and phosphorylated forms of mTORC1, p38MAPK, Akt, or PGC-1α (all p>0.10). Conclusions: Short-term nitrate supplementation, as a standalone treatment, may not be an effective way to improve mitochondrial function in patients with HFrEF and, as such, it may be clinically important to combine nitrate supplementation with other interventions known to affect mitochondrial function, such as exercise training. General Conclusions. Short-term inorganic nitrate supplementation had no effect on exercise tolerance (Study 1-Chapter 4), peripheral tissue oxygenation (Study 1- Chapter 4), or mitochondrial respiration (Study 3- Chapter 6) in patients with HFrEF. However, it may have a meaningful clinical effect on Q̇and SV during submaximal exercise (Study 2- Chapter 5). It may also improve vascular function (Chapter 4), reduce TPR (Chapter 5) and reduce DBP and MAP during submaximal exercise (Chapter 5) in these patients. Overall the data suggest that nitrate supplementation may be used in conjunction with other pharmacological and non-pharmacological (exercise training) interventions to improve clinical outcomes in this population. This hypothesis should be explored in the future by conducting a large-scale clinical trial.

Objective: The purpose of this study was to investigate the effects of regular postexercise hot water immersion (HWI) on selected physiological adaptations and on exercise performance in a temperate environment in trained road cyclists. Methods: Fourteen male cyclists were assigned to either an HWI (n = 7) group or a control (CON, n = 7) group. Both groups completed 9 high-intensity interval training sessions (over 3 weeks), with each training session followed by sitting in a water tub for 30 min. Participants from the HWI group were immersed in 42°C water, whereas a thermoneutral water temperature of 34°C was used for the CON group. Core and intramuscular temperature were continuously recorded during the first water immersion session and for 30 min post-session. Before and after the intervention, the cyclists performed a 20-km time trial test and an incremental test to exhaustion to determine lactate turn point, maximal oxygen consumption and peak power output. Venous blood at rest was sampled pre- and post-intervention to assess changes in plasma volume. Muscles biopsies were obtained from the vastus lateralis pre- and post-intervention to assess changes in mitochondrial function. Variables were analysed using t-test and two-way repeated measures analysis of variance. Results: Intramuscular temperature was significantly higher in the HWI than in the CON group at the end of the water immersion treatment (37.8 ± 0.4 vs 36.2 ± 0.5 °C, p=0.001) and 30 min post-immersion (36.7 ± 0.4 vs 35.1 ± 1.2 °C, p=0.01). In addition, HWI group had significantly higher core temperature immediately post-immersion than the CON group (37.8 ± 0.4 vs 37.1 ± 0.2 °C, p=0.01). However, all other measures were not significantly different between the groups. Nevertheless, there was a significant improvement in 20-km time trial performance in both the HWI (2009.8 ± 147.3 vs 1977.5 ± 134.5 seconds, p=0.01) and the CON group (2010.4 ± 182.3 vs 1974.2 ± 185.7 seconds, p=0.04). Conclusion: Three weeks of high intensity interval training led to an improved 20-km time trial performance, but the post-exercise HWI protocol used in this study did not provide additional performance benefits.

There is an emerging consensus that sleep is an important part of the post-exercise recovery process for athletes. Evidence suggests that a lack of sleep, or sleep of poor quality, can negatively influence markers of physical, physiological, and perceptual recovery that may impact the subsequent training and performance outcomes of athletes. Moreover, recent findings suggest that increasing total sleep time can improve performance, yet comprehensive evidence is lacking. This has seen an increased focus on the investigation of the sleep behaviours of athlete populations; however, this research often does not consider many important contextual factors, such as the physical sleep environment, competition factors including location, travel and timing, and training-related factors like periodisation and training load exposure. Furthermore, little is known about the physical and physiological influences of sleep on the post-exercise recovery process, and information regarding the amount of sleep that is required to maximise recovery and athletic performance is lacking. The aim of the first study in this thesis was to investigate the influence of physical sleep environment during a pre-season training camp on the sleep behaviours of professional Australian Rules footballers. The results of Study 1 (Chapter 4) describe the sleep behaviours of professional Australian Rules footballers between the home environment and a pre-season camp environment, both during the pre-season training period. Australian Rules footballers went to bed and woke earlier when on camp, spending longer in bed without a significant increase in sleep duration, caused by significantly increased wake after sleep onset. Relative changes to time in bed and wake after sleep onset on camp had a strong negative correlation with absolute home values, suggesting those who spend longer time in bed at home are more likely to experience reduced time in bed in the camp environment. Although there was no significant change in total session rating of perceived exertion (s-RPE) training load, when accounting for daily variations of within-player s-RPE load, both increased and decreased s-RPE load had weak correlations with changes in total sleep time in the home environment. Comparatively, in the camp environment, decreases in s-RPE load displayed a moderate positive relationship with total sleep time, whereas increases in s-RPE load displayed moderate negative correlation with total sleep time. However, daily ambient temperature was ~5°C hotter during the camp environment, compared to the normal home environment, which may have influenced results. A change in physical sleep environment, without external influences such as circadian phase-shifting, altered training schedules or increased total training load reduces the quality of sleep and effects the attainment of increased duration of sleep, despite spending longer periods of time in bed. Furthermore, the individual variation in response to a change in environment stresses the importance of assessing sleep on a case-by-case basis, especially if assessment leads to the provision of interventions designed at improving the sleep of athletes during time spent in unfamiliar physical sleeping environments. The aim of the second study in this thesis was to investigate the role that individual contextual factors (age and chronotype) and environmental factors (competitive matches, competition level, and competition location) have on the sleep behaviours across the pre-season and in-season periods in professional Australian Rules footballers. Study 2 (Chapter 5) found that the individual-specific factor chronotype influences the sleep behaviours of Australian Rules footballers. Furthermore, players went to bed and woke later, resulting in increased time in bed and total sleep time, during the in-season compared to the pre-season. On the night before a match, and the two nights following a match, players spent longer in bed and obtained more sleep compared to the pre-season. In contrast, on match nights players spent less time in bed and obtained less sleep, compared to the night before and the two nights following a match; but obtained similar sleep durations on match nights to during the pre-season. No differences in sleep behaviours were observed between matches played at home or away; however, time in bed and sleep duration were reduced following National-level competition, compared to State-level competition. Collectively, these results suggest that individual chronotype needs to be considered in the evaluation of athlete sleep behaviours, and that sleep behaviours vary between season phases, nights surrounding competition, and between competitive levels. The aim of the third study in this thesis was to determine the influence of changes in load variables during both the pre-season and in-season across 1-, 7-, 14-, 21- and 28-day periods and their relationships with objectively measured sleep behaviours in Australian Rules footballers. Study 3 (Chapter 6) found that same-day increases in volume (total distance and s-RPE) and intensity (relative total distance, high-speed running and very high-speed running) have negative associations with sleep behaviours during both the pre-season and in-season. Cumulative 7-day loads during the pre-season have minimal associations with sleep behaviours, whereas sleep duration was negatively associated with higher 7-day cumulative loads during the in-season period. Increased load measures detrimentally influence sleep behaviours over 14-day, 21-day and 28-day cumulative periods during the in-season. These results suggest that heightened short- and long-term exposure to increased loads have a negative effect on the sleep behaviours of Australian Rules footballers. Therefore, consideration of both the acute and cumulative demands of training and competition should be made in the context of monitoring of Australian Rules footballers sleep. The aim of the fourth study in this thesis was to determine the effect of a single night of sleep extension on physiological, physical, and perceptual recovery. Study 4 (Chapter 7) found that whilst the novel high-intensity intermittent exercise session induced similar post-exercise responses to that of team-sport competition, a single night of increased sleep duration (sleep extension) did not influence markers of neuromuscular, autonomic, perceptual, and hormonal function and status on the morning following a session of high-intensity interval exercise under laboratory-controlled conditions. Longer periods of sleep-intervention may be required to have a beneficial effect on markers of recovery and function following exercise. Finally, the aim of the fifth study in this thesis was to determine the effects of multiple days of post-exercise sleep extension (where a total of 10 h per day for 3 days was obtained) on the status of physiological, physical, and perceptual recovery and physical performance. Study 5 (Chapter 8) found that 2-hour afternoon naps (following 8 h of sleep each night) improves the recovery rate of neuromuscular function. Furthermore, both overnight sleep extension (10 h) and afternoon naps improved the recovery of sprint performance following a session of high-intensity interval eercise that was followed by a night comprised of a 6-hour sleep. Overnight sleep extension appears to enhance recovery of perceptual wellbeing measures after, compared to afternoon naps. These results suggest that both overnight extension and afternoon naps have a postive influence on post-exercise recovery. However, caution should be exercised, as afternoon naps may increase sleep onset latency and wake after sleep onset, and reduce sleep efficiency of subsequent night sleep when performed on consecutive days.

In this thesis, I examined the impact on flow and shooting performance of imagery interventions designed to increase proposed antecedents of flow, illuminating mechanisms underlying the positive experience of flow in basketball players. Flow is a positive psychological state that is associated with high levels of enjoyment, intrinsic motivation, and performance, so athletes and coaches aim to optimize flow. Imagery is a powerful technique that has been shown to enhance performance and flow state in sport. Stavrou and Zervas (2004) proposed that five dimensions of flow are antecedents that can enhance the experience of flow. This thesis comprises three studies with parallel structure, using a pre-test, intervention, post-test study design. In pre-test and post-test, participants performed 40 shots (eight trials x five locations around the basketball key) at 4.5 metres (2-point) and 40 shots (same five angles) at 6.75 metres (3-point). In the Imagery condition, participants completed six 15-minute imagery sessions over two weeks, focusing on the designated antecedent dimension. The Video Placebo condition involved equivalent attention focused on watching video of basketball game competition. Participants were randomly assigned to conditions. I used Two-way Mixed-design ANOVA and Tukey post hoc tests to examine shooting performance and all nine flow dimensions in all three studies. In Study 1, I examined whether the imagery of three flow dimensions, challenge-skill balance (C-S balance), clear goals, and unambiguous feedback, enhanced flow states and increased shooting performance with 18 male and 8 female basketball players. The Flow Antecedents Imagery condition involved imagining clear goals and unambiguous feedback of shooting in an individualised C-S balance context. The Video Placebo condition involved equivalent time watching video of elite performers shooting in competition. Results indicated that the Flow Antecedents Imagery intervention enhanced the three targeted flow dimensions, C-S balance, clear goals, and unambiguous feedback, as well as global flow with significant interaction effects. The Flow Antecedents Imagery condition improved 2-point, 3-point, and total shooting significantly more than the Video Placebo condition. In Study 2, I examined the impact of an imagery intervention designed to increase total concentration on flow and performance with 18 male and 12 female basketball players. Flow is the feeling athletes get when they are totally absorbed in their sport, whether in training or competition. Thus, total concentration is a key antecedent dimension of flow. The Flow Antecedents Imagery condition involved imagining total concentration on shooting. The Video Placebo condition involved equivalent time watching video of game competition. Results indicated that the Flow Antecedents Imagery condition increased all nine flow dimensions and improved 2-point and total shooting significantly more than the Video Placebo condition. In Study 3, I examined the impact of an imagery intervention designed to increase sense of control on flow and performance with 16 male and 14 female basketball players. This involves imagining individuals feeling calm and confident during basketball shooting performance. The Flow Antecedents Imagery condition involved imagining feeling relaxed, calm, and confident while shooting. The Video Placebo condition involved equivalent time watching video of game competition. Results showed that the Imagery condition improved 2-, 3-point, and total shooting significantly more than the Video Placebo condition. Imagery of sense of control enhanced basketball-shooting performance, but significant pre-test differences interfered with effects of imagery on flow dimensions. In the three studies in this thesis, I found substantial evidence supporting the role of imagery of the five antecedents of flow as an effective technique for enhancing global flow state, flow state dimensions, and performance, which should promote further research on the antecedents of flow in sport.

Goal-kicking is an important skill in Australian Football (AF), accounting for approximately 62% of points scored during a match (Anderson et al., 2018). Despite its importance, little biomechanical research has examined the key technical characteristics underpinning the skill. The aims of this thesis were to validate a methodological approach to enable quantification of goal-kicking kinematics in a field environment, and examine goal-kicking technique and identify technical factors associated with accuracy. In Chapters 3 and 4, the Xsens inertial measurement system (IMS) was validated against a Vicon motion capture system (MAS) when measuring lower extremity and pelvis kinematics. Trivial to small mean differences (0.2-10.1%) and measurement error (0.1-7.9%) were found between the IMS and MAS across all parameters, advocating the use of IMS to quantify kicking kinematics. In Chapter 5, the effect of modifying the task constraints on accurate goal-kicking was explored. Increasing the distance of the shot from goals (30 m to 40 m) required substantially greater joint range of motion (knee and hip), with higher linear (foot speed) and angular (knee and shank) velocities. Altering the angle of the shot (0 to 45°) had no substantial influence on accurate goal-kicking technique. Findings indicated adjustments in goal-kicking technique may be required dependent on the location of the shot. In Chapter 6, 18 elite to sub-elite AF players performed 15 x 30 m goal-kicks in-front of goals and technique was examined on group-basis. A number of substantial kinematic differences were identified between accurate and inaccurate goal-kicks. For example, accurate goal-kicks were characterised by substantially less kick-leg joint range of motion (ankle, knee and hip), lower linear (com, foot speed) and angular (knee and shank) velocities, with less support-leg knee flexion during the kicking phase. In addition, a number of substantial linear and quadratic relationships were reported between technical parameters and accuracy. Findings indicated that many factors influence goal-kicking accuracy in AF; ranging from technical errors in the player’s approach, configuration of their support-leg and kick-leg motions, through to follow-through position. In Chapter 7, goal-kicking data from chapter 6 was examined on individual-basis. All players demonstrated substantial kinematic differences between accurate and inaccurate goal-kicks, along with substantial relationships between kinematic parameters and accuracy, but these were individual-specific. A combination of both a group and individual-based analysis provided a more thorough understanding of technical factors which influence goal-kicking technique in AF. The body of work in this thesis provides: 1) validation of a methodological approach to quantify kicking biomechanics, and 2) a comprehensive understanding of technical factors associated with goal-kicking accuracy in AF, and 3) recommendations for both research and coaching practice.

Introduction: Monitoring athlete performance in training and competition can assist conditioning professionals and sport scientists to enhance performance outcomes whilst also minimising the risk of injury, illness and non-functional overreaching. Yet the monitoring of athletes to improve position-specific match performance has never been investigated in the team-sport of netball. Aims: This thesis aims to examine the extent to which three common forms of athlete monitoring relate to match performance in state-level netball athletes, providing practitioners with guidelines for maximising performance outcomes. Study 1 - Purpose: To determine any substantial differences in physical capacities between positional groups within the state-level netball cohort of this thesis, to justify an investigation into position-specific monitoring strategies for enhancing match performance. Methods: Forty-six state-level netball athletes completed physical capacity assessments in the second week of their preseason, over two-seasons. Tests included stature, 20 m sprint (with 5 m and 10 m splits), 505-change-of-direction, countermovement jump, single-leg bounding and the Yo-Yo Intermittent Recovery Test Level One. Results: There were numerous substantial differences between positions with mid-court athletes typically displaying the greatest overall physical capacity followed by defenders then shooters. Study 2 - Purpose: To investigate the reliability of a tracking metric (Player LoadTM) within a court-based sport environment, to determine its efficacy for objectively investigating activity profiles within state-level netball matches by position. Methods: Eighteen state-level netball athletes’ accelerations were tracked with two accelerometers, each housed within an athlete tracking unit (OptimEye S5, Catapult Sports, Australia), taped together with axes aligned during netball match-play. Results: The inter-device Player LoadTM was reliable with the typical error was 5.9 (90% compatibility limits (CL) 5.2 to 6.7), with the CV 4.8% being well below the SWD of 8.2%. Study 3 - Purpose: To utilise the Player LoadTM metric to determine substantial differences between positions by analysing the peak intensities during state-level netball matches, to further justify an investigation into position-specific monitoring strategies for enhancing match performance. Methods: Twenty-eight netball athletes wore an accelerometer (S5 Optimeye, Catapult sports) for all matches, in one season. Peak Player LoadTM was quantified over 30-seconds and one to ten-minute time periods. Results: Across all time periods post 30-seconds, only one comparison was not meaningfully different i.e., three-thirds v two-thirds at the one-minute timepoint (effect size: 0.27, CL -0.05 to 0.60). Study 4 - Purpose: Following a strong justification for investigating position-specific monitoring strategies to enhance match performance, this study aimed to determine the extent to which performance indicators, coach ratings and their combination predict match outcome in netball. Methods: Two seasons worth (39-40 matches) of performance indicators and coach ratings were collected for players of a state-level netball club with one team in each of three divisions (27 championship, 23 division-one, and 19 19-&-under females). There were five performance measures being coach weighted performance indicators (CWPI) and a novel equal weighting (EWPI); coach ratings of overall performance; multiple linear regression was also used to derive correlations for combinations of coach rating with the CWPI and with the EWPI. Results: For team performance the combination of EWPI and coach rating was the strongest predictor of points differential. No measure of position-specific match performance was consistently related to points differential across all three teams. Study 5 Purpose: The aim of this study was to examine the extent to which three monitoring strategies predict five measures of position-specific match performance. Methods: State-level netball athletes (n = 46, age = 20.29 ± 4.15 years) were monitored over a two-year period and were split into three position groups (defenders, mid-courts and shooters). Training load (sessional rate-of-perceived exertion), wellness questionnaires and CMJ were collected. All five predictor measures from Study 4 were the criterion for position-specific match performance. Results: Training load dose was the only monitoring tool related to match performance for all three position groups. There were no substantial relationships between wellness questionnaires and match performance for any group. Only shooters were found to have substantial relationships between CMJ and match performance. Thesis conclusions: Netball athletes have substantial differences in physical capacities dependent on positions played. The peak intensities reached during match-play is also substantially different for positions. There is no superior approach for match performance assessment in netball for predicting points differential. The monitoring of training load doses provides important information for coaching and conditioning staff to predict future match performance for all position groups. The use of wellness questionnaire data does not provide useful information for predicting an athlete’s match performance. Finally, only shooters demonstrated a relationship between CMJ and match performance. The findings of this thesis indicate that to enhance match performance in netball, a position-specific monitoring approach is required.

The aim was to produce three quality publications including; a review of literature publication and two original studies designed to examine the effects of pressure on free-throw performance, particulary the phenomenon of choking, in the sport of basketball. Pressure when FT shooting is generally experienced by basketball players, irrespective of the level of participation, and resultant choking can affect game outcome and diminish personal enjoyment (Gómez, Lorenzo, Jiménez, Navarro, & Sampaio, 2015; Worthy, Markman, & Maddox, 2009). The theoretical framework for the current study was a triangulated approach by examining choking from multiple perspectives with the common focus on choking in the task of basketball free throw shooting. The combination of a traditional quantitative approach (Study 1) and a less traditional qualitative approach (Study 2) were used to potentially provide perspectives on choking to illuminate possible consistencies and inconsistencies in how choking is experienced. Study 1 was designed to capitalize on the depth of athletes’ knowledge using a small number of elite athletes and reflected a predominantly inductive logic. The findings of this study informed a deeper understanding of how basketball players typically deal with choking and potentially present new knowledge and strategies relevant to alleviate choking within and beyond the sport of basketball. The elements of knowledge, transfer and exchange, the process of acquiring, developing, sharing and applying knowledge was used to question how the results can inform practice in the ‘real world’. In keeping with triangulation, the insider perspective used in Study 1 was equivalent to a ‘bottom up’ explanation of choking. Conversely, Study 2 was designed to more actively control variables in a quasi-experimental manner and was linked in design to the results from Study 1. Study 2 was designed to examine the effects of physical exertion on choking in conjunction with psychological using a larger population of competitive recreational student-athletes and reflected a predominantly deductive logic. More specifically, the aim of the first study was to investigate ‘insider’ perspectives of elite basketball players regarding perceptions of pressure and the associated phenomenon of choking in basketball free-throw shooting. Seven elite basketball players (1 female and 6 males; Mage = 33.3, SD = 5.4) were recruited through snowball sampling. In-depth semi- structured interviews were conducted to enable participants to reflect on experiences of pressure and explanations of how to avoid choking. The data were thematically analysed, with six themes identified; choking definitions, antecedents, personality, automaticity, mental skills, and management strategies. The findings are discussed, especially in the context of mental skills, to reduce choking-susceptibility, and to recommended strategies for players, coaches and sport psychologists to consider when managing chronic choking. More specifically, the aim of the second study was to examine the influence of physical exertion and pressure as potential antecedents of choking in basketball free-throw shooting. A within-subjects design was implemented with 50 student-basketball players who completed 40 basketball free-throws in four manipulated conditions: higher pressure-running, higher pressure-no running, lower pressure-running, and lower pressure-no running. A repeated measure analysis of variance revealed that participants scored significantly lower in the higher-pressure conditions than the lower-pressure conditions. Furthermore, participants scored significantly higher in the no-running conditions compared to the running conditions. The current study was the first to examine the effects of physical exertion on performance in pressure situations. The applied implications of these results are discussed and tentative conclusions drawn for the relevance to players, coaches and sport psychologists. The participants in Study 1 provided unique insights based on their extensive experience performing under pressure at the highest levels of basketball. Participants were aware of the importance of mental skills but were not necessarily sufficiently informed or able to rectify choking without further assistance. The results of Study 2 contributed useful new information and insights into the link between physical exertion and choking. These results provide a new avenue for researchers interested in further examining physical exertion and fatigue as contributing to under-performance under pressure. Overall, the two studies broaden the knowledge regarding the triggers and underlying mechanisms of choking, and also enrich the strategies that athletes can use to optimise their performances. I expect that the current findings will be able to build capacity in assisting those players who experience difficulties in converting critical free-throws. Finally, the results of the current study assist athletes, coaches, and applied sport psychologists to better understand the deleterious effects of pressure in sport and suggest possible solutions to manage them.

Polycystic Ovary Syndrome (PCOS) is a common and complex endocrinopathy. The proposed pathophysiology of PCOS is a synergistic relationship between perturbed gonadotropin pulsatility, hyperandrogenism, insulin resistance and inflammation. However, the nuances of these relationships are yet to be fully elucidated. The biological origins of PCOS are driven by heritability and a polygenic predisposition that is exacerbated by environmental factors (e.g. obesity). Therefore, the aetiology of PCOS is considered multifactorial. While familial clustering of PCOS symptoms is well documented, providing evidence for a genetic contribution to the condition, lifestyle factors also mediate the influence of the underlying mechanism of PCOS. These mechanisms likely involve epigenetics, which are the molecular interactions between genetics and lifestyle. Epigenetic modifications, like DNA methylation alter chromatin structure and gene expression. These DNA modifications are associated with the pathogenesis of obesity-related chronic diseases, yet there is limited evidence in PCOS. Therefore, the overall aim of this thesis was to assess different molecular mechanisms that are postulated to contribute to the aetiology of the syndrome by i) conducting an overview of systematic reviews to synthesise the current evidence and quality of evidence for the relationship between candidate gene polymorphisms and PCOS, ii) investigate the differences in global DNA methylation in specific immune cell populations in women with and without PCOS, iii) identify differences in genome-wide DNA methylation patterns and gene expression in immune cells of women with and without PCOS, iv) to further explore molecular mechanisms of PCOS-specific insulin resistance. My research concluded that there is very little evidence in the literature to ascribe specific genetic variations in PCOS, clearly highlighting a need for standardisation in the design and analysis of genetic association studies in PCOS. I also report that immune cells in women with PCOS display hypo-methylation in T helper cells, T cytotoxic cells, B cells and monocytes. Furthermore, immune cells displayed genome-wide differential gene expression and DNA methylation patterns in T helper cells in women with PCOS. Finally, I show that PCOS-specific insulin resistance may be regulated distal to Akt via interactions with the TGFβ signalling network. In summary, this thesis advances the fundamental understanding of the molecular basis of the aetiology of PCOS and offers a novel hypothesis to drive future research to better understand the syndrome and PCOS-specific insulin resistance.

Multi-Sport Holiday Programmes (MSHPs) are one of the most popular and prevalent styles of holiday programme for Victorian children. To date, no research has explored MSHPs, and the research on holiday programmes within Australia remains vague. Analysis of MSHPs will contribute to the future direction of children’s organised sport, socialisation, and childcare research. This thesis explores the emergence of MSHPs and considers 1) what political and social factors support their emergence, and, 2) What knowledge and practices pervade MSHPs. This thesis begins by exploring the privatisation of the childcare market in Australia, and how the advancement of children’s sport and physical education policy contributed to the emergence of MSHPs. Although the amount of political commentary surrounding how and why children should engage in sport has progressed, the literature review alludes to a lack of research on holiday programmes in Australia. Considering that 25% of children aged 5-9 years engage in formal care during the holiday period, this poses a significant gap. To address this gap, an examination of MSHPs practices and procedures occurred. The findings show that MSHPs are sites of socialisation that reproduce narrow perspectives of health, gender, and the body. These findings are similar to past research conducted in playground environments, physical education, and junior sports programming. MSHPs do not exist in a silo, and future research should consider them as part of broader children’s sport and physical activity research which investigates discourses of meritocracy, masculine hegemony, and healthism. Thus, recommendations arising from this thesis are twofold: 1) Consider the effects of socialisation within MSHPs alongside research undertaken in schools, sports clubs, and the playground. 2) Analyse and provide recommendations on the juxtaposition of children’s sport/physical education policy and the distribution of federal and state funding for elite sport.

In dragon boat racing, boat speed is generated by paddle propulsion produced by human movement. However at the fundamental level it is the interaction of the paddle with water that produces the forces generating boat speed. Literature on the biomechanics of paddle propulsion is sparse and is concerned predominantly with human movement and not with the fundamentals of paddling. This thesis examines the biomechanics of dragon boat paddling from the perspective of the paddle. Kinetic and kinematic paddle data were collected sequentially for each test participant from two dragon boat crews via 30 s maximum effort paddling tests. A custom built strain-gauged paddle sampled the paddling forces at 200 Hz whilst a stationary video camera (Sony HDR-HC7) recorded a single representative racing paced paddling stroke at 200 Hz. A light flash recorded by the video camera and its trigger signal recorded by the force data collection system ensured synchronisation. Excel spreadsheets converted the data into kinetic and kinematic paddle parameters for each study. Study one operationalised a qualitative coaching model for teaching paddlers a good dragon boat paddling stroke and produced strong support for the coaching model via a statistical comparison of more skilled paddlers with paddlers less skilled. More skilled paddlers produced significant superior results for paddle reach at water contact, rate of force development on water entry, maximum paddle force, drive impulse and drive impulse rate, force rate reduction at paddle exit and paddle impulse during recovery. Study two investigated the kinetic, kinematic and temporal paddle parameters that differentiate a more successful dragon boat racing crew from a less successful crew. The more successful racing crew produced significant superior results for rate of force development during water entry, average drive force, average peak to drive force ratio, rate of force reduction at paddle exit, paddle reach at water contact, paddle angle at maximum force, average paddle angular velocity in water, paddle displacement on the water surface, the stroke length, and the time duration of the catch and the paddling stroke. Study three examined the kinetic and temporal paddle parameters that differentiate more skilled paddlers from the less skilled. More skilled paddlers produced significant superior results for the rate of force development during paddle entry, maximum paddle force, paddle force at vertical position, average force during the catch and drive phases of the paddling stroke, average peak to drive force ratio, rate of force reduction at paddle exit, drive impulse, drive impulse rate, stroke impulse during recovery. And the time duration of the catch and drive phases of the addling stroke. Study four, the final study, established the kinematic paddle parameters that differentiate more skilled paddlers from paddlers less skilled. The more skilled paddlers produced significant superior results for paddle reach at water contact, average paddle angular velocity in water, paddle displacement on the water surface and paddle angle at water exit. Together these four studies provide a biomechanical foundation for the sport of dragon boat racing. Coaches and paddlers can use the findings of this thesis to improve paddling technique, paddling skill and racing performance.

In recent years exercise pacing research has identified numerous factors that can influence exercise intensity and improve overall performance. However, the list of factors that can influence pacing is far from comprehensive or extensively researched. Subsequently, this thesis aimed to investigate pacing factors which have not yet been empirically or functionally tested. Specifically, the following aspects were identified for investigation; the role of exercise experience, exercise-induced pain, and athlete motivation during competition. These factors were chosen for both the crucial role they play within theoretical pacing models and for the way they influence different aspects of exercise pacing (i.e. variables that are internal and external to the athlete during exercise, as well as prior to exercise). By selecting different factors, this ensured a holistic approach was taken to investigating the theoretical pacing literature. The first factor investigated was an athlete's prior experience of the exercise, which is vital to anticipatory regulation of the task at hand and consequently, the development of a pacing strategy. Secondly, exercise-induced pain was chosen, as this a factor that is internal to the athlete during exercise. This sensation is key to the models of pacing and plays a significant role in exercise regulation. However, transcutaneous electrical nerve stimulation has not yet been fully tested as a method to reduce exercise-induced pain and how this can impact performance. Lastly, competition is an external factor during exercise, which has been known to influence pacing and performance for many years. However, the physical presence of competitors in ecologically valid circumstances, as well as interplay of social and physiological factors have not been rigorously investigated. Study one. Exercise performance is reproducible in experienced athletes; however, less trained participants exhibit greater variability in performance and pacing. To reduce variability, it is common practice to complete a familiarization prior to experimental testing. However, there are no clear guidelines for familiarizing novice participants to a cycling time-trial (TT), and research findings from novice populations may still be influenced by learning effects. Accordingly, the aims of this study were to establish the variability between TTs after administering differing familiarization protocols (duration or type) and to establish the number of familiarization trials required to limit variability over multiple trials. Thirty recreationally active participants, with no prior experience of a TT, performed a 20-km cycling TT on five separate occasions, after completing either a full (FF, 20-km TT, n=10), a half (HF, 10-km TT, n=10) or an equipment familiarization (EF, 5-min cycling, n=10). Variability of TT duration across five TTs was the lowest after completing FF (P = 0.69, ηp2 = 0.05) compared to HF (P = 0.08, ηp2 = 0.26) and EF (P = 0.07, ηp2 = 0.21). In the FF group after TT2, the effect size for changes in TT duration was small (d < 0.49). There were large differences between later TTs in HF (d = 1.02, TT3-TT4) and EF (d = 1.12, TT4-TT5). The variability in mean power output profiles between trials was lowest within FF, with a similar pacing profile reproduced between TT3-TT5. Familiarization of the exercise protocol influenced the reproducibility of pacing and performance over multiple, maximal TTs, with best results obtained after a full experience of the exercise compared to HF and EF. The difference of TT1 to later TTs indicates that one familiarization is not adequate in reducing the variability of performance for novice participants. After the FF and an additional TT, performance changes between TTs were small. However, a reproducible pacing profile was not developed until after the FF and two additional TTs. These findings indicate that a minimum of three full familiarizations are necessary for novice participants to limit systematic error before experimental testing. Study two. Afferent information from exercising muscle contributes to the sensation of exercise-induced muscle pain. Transcutaneous electrical nerve stimulation (TENS) delivers low–voltage electrical currents to the skin, inhibiting nociceptive afferent information. The use of TENS in reducing perceptions of exercise-induced pain has not yet been fully explored. This study aimed to investigate the effect of TENS on exercise-induced muscle pain, pacing strategy and performance during a 5-km cycling time trial (TT). On three separate occasions, in a single-blind, randomized and crossover design, 13 recreationally active participants underwent a 30-min TENS protocol, before performing a 5-km cycling TT. TENS was applied to the quadriceps prior to exercise under the following conditions; control (CONT), placebo with sham TENS application (PLAC), and an experimental condition with TENS application (TENS). Quadriceps fatigue was assessed with magnetic femoral nerve stimulation assessing changes in potentiated quadriceps twitch force at baseline, pre and post exercise. Subjective scores of exertion, affect, and pain were taken every 1-km. During TTs, application of TENS did not influence pain perceptions (P = 0.68, ηp2 = 0.03). There was no significant change in mean power (P = 0.16, ηp2 = 0.16) or TT duration (P = 0.17, ηp2 = 0.14), although effect sizes were large for these two variables. Changes in power output were not significant but showed moderate effect sizes at 500-m (ηp2 = 0.10) and 750-m (ηp2 = 0.10). Muscle recruitment as inferred by electromyography data was not significant but showed large effect sizes at 250-m (ηp2 = 0.16), 500-m (ηp2 = 0.15) and 750-m (ηp2 = 0.14). This indicates a possible effect for TENS influencing performance up to 1-km. Yet, overall, these findings do not support the use of TENS to improve 5-km TT performance. Study three. The aim of this study was to investigate time-trial (TT) performance in the presence of one competitor and in a group with competitors of various abilities. In a randomized order, 24 participants performed a 5-km cycling TT individually (IND), with one similarly matched participant (1v1), and in a group of four participants (GRP). For the GRP session, two pairs of matched participants from the 1v1 session were used. Pairs were selected so that TT duration was considered either inferior (INF) or superior (SUP) compared to the other pair of participants. Overall, TT duration (P = 0.86, ηp2 < 0.01) was not different between conditions, whilst heart rate (HR) was significantly greater in GRP compared to IND (P < 0.01, ηp2 = 0.16). For INF, a large effect size for both mean power (P = 0.07, ηp2 = 0.15) and HR (P = 0.05, ηp2 = 0.16), indicates greatest effort in GRP. Pacing behaviour was affected by competition but similar in 1v1 and GRP for SUP, whilst large effect sizes indicate an increased power output in the initial 750-m for INF in GRP. Additionally, for INF, there was a significant correlation with ego orientation for an increase in TT duration between the GRP session and both the IND (r = 0.43, P = 0.04) and 1v1 (r = 0.54, P = 0.01) sessions. For INF participants, the intensity was increased when competing in GRP. Yet, the presence of the SUP competitors resulted in lesser performance improvements for ego oriented INF participants. These findings demonstrate that consideration should be given to the ability of competitors in a group setting to provide adequate motivation. Overall this thesis provides novel insight into pacing factors that have previously not been fully understood. This research is of importance as a greater understanding of how exercise is self-regulated is crucial to unlocking the potential for increased exercise performance. The main results and conclusions of this thesis shed light on the highlighted pacing factors of experience, exercise-induced pain and competition, and how these can impact on performance during self-paced cycling time-trials. Accordingly, these findings provide information to benefit the development of sound experimental protocols as well as providing a mechanistic understanding of the development of exercise scenarios and interventions that can be beneficial to performance outcomes.

National sporting organisations such as the AFL invest significant resources into establishing talent identification (TID) and talent development models to ensure the future success of their sport. The process usually involves predicting player potential through subjective assessments of game performances in combination with objective inputs inclusive of physical fitness testing, movement ability assessments, and match activity profiles. However, elite sporting performance is the product of a player’s ability to overcome and master the dynamic interactions between organismic, task, and environmental constraints that may impede or facilitate physical fitness and skill development. Organismic constraints such as growth, maturity, and learning stages of individual players can all influence physical fitness, movement ability, and match activity profiles. Specific environmental constraints include differences in game play, skill level, game rules and policies, and field sizes. Task constraints are the limitations imposed by a set task, for example; the goals and rules of AFL, the sporting actions required, and the physical fitness qualities needed for high-level match performance. Of particular interest is the as relative age effect (RAE), a selection bias among players of differing skill and maturity levels caused when adolescent players are grouped into annual age-grouped teams. The extent to which these constraints contribute to variations in physical fitness and match activity between levels of junior AF competition is unclear. This thesis investigates the interactions between physical fitness characteristics, the RAE, and match activity profiles across multiple levels of the AFL participation pathway, and the subsequent implications for player TID and development. The first study was a systematic review examining physical fitness measures of players across the AFL participation pathway levels to quantify longitudinal changes observed in physical fitness characteristics. Only studies examining physical fitness tests were included, with 27 meeting the inclusion/exclusion criteria. Sprint time (20-m) was the most reported test across the AFL participation pathway, followed by vertical jump (VJ), AFL agility, and 20-m multi-stage fitness test (MSFT). The fastest times for 20-m sprint were for elite AFL players (range 2.94 – 3.13 s), with local level players the slowest (3.22 – 4.06 s). State Junior Under (U) 18s had higher jumps than senior players; with the lowest jumps reported for Local U10s (range 31- 66 cm). Interestingly, no elite-level data were reported for the AFL agility or 20-m MSFT, with AFL agility times only reported for talent pathway levels (8.17 – 9.12 s). However, 20-m MSFT scores were reported across the junior levels of the AFL participation pathway (6.1 – 13.5 shuttles). Talent squad players exhibit similar test scores between competition levels irrespective of the physical fitness test, with the exception of 20-m sprint and VJ. It was suggested that physical tests can discriminate between local participation level players, but are less useful within the AFL talent pathway. Study II examined the influence of age-policy changes on the RAE across the AFL talent pathway. The study design was a retrospective cross-sectional analysis of junior AFL players attending the annual National Draft, State, and State U16 combines between 1999 and 2016. Birth-date data was obtained for players attending the AFL State U16 (n = 663), State (n = 803), National (n = 1111) combines, with comparisons made against corresponding aged-matched Australian general population birth-rates. Specifically, Under 16s and State players had greater birth frequencies (2% to 4.9%, p < 0.05) for earlier months in the selection year. Age-policy changes at the National level reduced birth distribution bias for some months; however the RAE remained for other months (March 3.9%, June 6.1%, and July 4.3%, p ≤ 0.05). State U16s and National players had 2- 9% lower birth frequencies for the later months in the selection year compared general population. It seems that selection bias towards older players is instigated at the AFL’s State U16, and maintained through to the State and National levels, with age-policy changes only partially successful at addressing the RAE at the National level. Study III investigated the levels of association between physical fitness and match activity profiles of players within the AFL participation pathway. A total of 287 players across seven pathway levels were assessed on the 20-m sprint, AFL agility, VJ and running VJ, 20-m MSFT, and Athletic Abilities Assessment (AAA). Match activity profiles were obtained from global positioning system (GPS) measures; relative speed, maximal velocity, and relative high speed running (HSR). Correlational analyses revealed moderate relationships between sprint and jump test scores and match activity profiles in Local U12, Local U14, National U16 and National U18s (r = 0.32-0.78, p ≤ 0.05), but not jump tests in National U18s. AFL agility time was moderate-to-strongly associated with all match activity measures in Local U12, Local U14, Local U18, and National U16s (r = 0.37-0.87, p ≤ 0.05), and with relative speed in Local U18s (r = 0.84, p ≤ 0.05). Relative speed and HSR were moderate-to-strongly associated with 20-m MSFT in Local U14, Local U18, and National U18s, and AAA score in Local U12, and Local U18s (r = 0.41-0.95, p ≤ 0.05). Match activity profile demands increased between Local U12 and National U16s, then plateaued across the talent pathway levels. Physical fitness seemed to relate more strongly to match activity profiles in younger adolescent and National level players’, therefore recruiters should consider the dynamic changes physical changes between AFL participation pathway levels. The final study examined the utility of physical fitness and movement ability tests in differentiating and classifying players into specific AFL participation pathway levels. Players (n = 293) completed the same physical fitness tests battery as Study III; 5-m, 10-m and 20-m sprint, AFL agility, VJ, running VJ, 20-m MSFT, and AAA. A multivariate analysis of variance between AFL participation pathway levels for each test was conducted, and a non-linear analysis (classification tree) determined the extent players could be allocated to relevant levels. The magnitude of the difference between physical fitness and movement ability was age-level dependent, with the largest standardised effects between Local U12, Local U14s, and older levels for most physical fitness tests (Effect Size (ES): -4.24 to 4.65). The 20-m, 5-m, AFL agility, 20-m MSFT, overhead squat, and running VJ (right) all contributed substantially to the classification model, with over half of the players accurately classified into the appropriate AFL participation pathway levels (57%). The National U16 players were most accurately classified based these tests (87%); however, no National U18 players were classified. Talent selectors should consider differences in physical fitness and movement ability patterns between players when selecting players into the talent pathway; however other contextual factors (i.e., skills, psychological, and socio-cultural factors) are needed to establish a multi-component TID model in older levels of the talent pathway. Physical development differences between players, age-grouped competition levels, and talent levels reported in these studies should be considered in the planning, implementation, and review of AFL development programs. Establishing associations between common physical fitness and movement ability tests used for TID in AFL and match activity profiles allows coaches and talent selectors to make more informed player selection decisions. Also, non-linear modelling facilitates TID decisions as it can highlight under or over-performing players; flagging them to selectors for further investigation of other contextual factors influencing a player’s potential. Future studies should focus on including more areas that encompass TID and development (i.e., skills, psychological, and socio-economic attributes) to provide a comprehensive understanding of the interactions that determine a player’s success at an elite level. This research is not limited to AFL, with the methods used having the potential to provide more informed TID and development processes across other sports.

The overarching aim of this thesis was to examine the usefulness of a variety of existing combat sport practice tasks using representative learning design (RLD) as a framework. To date, RLD has largely focused on ensuring practice tasks sample the physical task and environmental informational constraints that support behaviour in competition. While useful, such empirical work has neglected to consider the role of emotions in training design. This thesis contains three experimental studies examining affect and representative practice design using taekwondo as a task vehicle. The first study explored the impact of a competitive opponent on action selection and interpersonal behaviour in taekwondo by examining the behavioural correspondence between two common combat tasks: striking a representative dynamic target and a non-representative static target. Findings revealed that low behavioural correspondence between static and dynamic targets as emergent striking actions were uniquely constrained by each task. The second study compared the affective, cognitive and behavioural demands of combat practice relative to competition. The findings revealed that the affective and cognitive demands of practice do not represent competition and are associated with behaviour that does not represent how players act in competition. The final study tested the hypothesis that situational information could enhance the affective and cognitive demands of practice tasks by manipulating the presence of a live scoreboard. Results revealed that scoreboard presence lead to greater arousal and anxiety. These increased affective demands were associated with player behaviour that more closely represented the competition behaviour from the previous study. In summary, this doctoral thesis contributes to an expanding body of work that advocates the use of principled theoretical and methodological frameworks to design sports practice tasks. The specific contributions include i) how affect and cognition influence action selection and action fidelity, and ii) the conceptualisation and application of how the fundamental Brunswikian concept of situational information can add to the design of representative learning tasks. The findings of this thesis suggest that to design truly representative learning tasks, practitioners should sample information, action and affective constraints to create rich competition-like experiences in practice so that athletes think, feel and act like they would in competition.

The regulation of glucose uptake and mass in skeletal muscle are essential for the maintenance of functional capacity, general health, and quality of life. Skeletal muscle can be categorised into two major types, glycolytic and oxidative muscles. The regulation of muscle glucose uptake varies between the two muscle types, dependent on specific conditions, such as whether or not insulin is present, and whether the muscle is at rest or following exercise. Furthermore, muscle atrophy in response to disuse, disease or aging also occurs in a muscle type-specific manner. However, the exact mechanisms underlying these muscle type specificities still remain unclear. Emerging evidence indicates that undercarboxylated osteocalcin (ucOC), a hormone secreted from bone, may play a role in the regulation of muscle glucose uptake and muscle mass. The signalling pathways underlying the ucOC effect on muscle are not clear, but may include G protein-coupled receptor, class C, group 6, member A (GPRC6A) as the receptor, along with the activation of protein kinase B (Akt), extracellular signal-regulated kinases (ERK), 5' adenosine monophosphate-activated protein kinase (AMPK), protein kinase C (PKC), Akt substrate of 160kD (AS160), mammalian target of rapamycin complex 1 (mTORC1), and/or the class O of forkhead box transcription factors (FOXOs). It is also not clear whether the effect of ucOC on muscle glucose uptake and the loss of ucOC signalling during muscle atrophy are muscle type-specific, contributing to the muscle type specificities in glucose uptake regulation and muscle wasting, respectively. Therefore, this PhD thesis aimed to explore the link between ucOC and muscle glucose uptake (under various conditions) and muscle mass in glycolytic and oxidative muscles, as well as investigate the underlying mechanisms. The thesis contains four separate but related studies, all of which have been published in top journals in the area of bone and mineral research.

In team sports, the competition season requires a balance between training and recovery. To assist in this process, both internal and external load are quantified. External load can be measured using Global Positioning Systems (GPS) and sensors such as accelerometers. Internal load is commonly identified through session rating of perceived exertion (sRPE), biochemical response in addition to changes in performance tests. However, little is known about the interaction between training load, the response to this load, and performance. Study 1 determined the response of countermovement jump (CMJ) performance and salivary testosterone and cortisol to low, medium and high accelerometer derived PlayerLoad™ following football match play. Flight time:contraction time (FT:CT) was the most sensitive CMJ metric, with a dose-response reduction for 42h post-match. There were post-match increases in testosterone and cortisol irrespective of PlayerLoad™ level, and substantial variability which limits the usefulness of hormonal markers. Study 2 assessed the impact of training and competition load throughout a professional football season on FT:CT, testosterone, cortisol and testosterone:cortisol and match performance. The largest effects of internal load on performance occurred in the 3- to 14-day pre-match window. An association between increased load and lower rating of performance was identified in defenders, whilst strikers and wide midfielder’s performance rating was higher with higher load. Change in load did not substantially impact FT:CT or the hormonal response, and there was limited impact of these measures on performance. Study 3 examined the use of a commonly used football training drill; small sided game (SSG), for measurement of neuromuscular fatigue (NMF). Whilst high weekly load increased accelerometer derived metrics during the SSG, these modifications did not appear to be fatigue related. Lower FT:CT compared to baseline, was related to reductions in accelerometer derived variables during the SSG. The reductions in FT:CT and accelerometer variables in the SSG were followed by the same modifications to match activity profile. Therefore, a standardised SSG game may be a useful tool for the assessment of NMF. This thesis provides insights into the links between training and competition load, the response to that load, and the impact on performance in elite male football players. The results offer practitioners useful approaches to monitor athletes and maximise their performance. Finally, this thesis demonstrates the utility of an SSG for the assessment of NMF.

Across the football codes, kicking is the main skill used to score goals and pass between team members. Kicking with high ball velocity and high accuracy is required to kick to targets at far distances or reach a submaximal target in less time. The impact phase is the most important component of the kicking action: it is the only time a player forcefully contacts the ball to produce the flight path. Ensuring high impact efficiency and the appropriate combination of flight characteristics are imparted onto the ball during foot-ball impact is important for successful kicking. The aim of this thesis was to determine how foot-ball impact characteristics influences impact efficiency, ankle plantarflexion, ball flight characteristics and kicking accuracy. By using a mechanical kicking machine to systematically explore impact characteristics and performing an intra-individual analysis of human kickers, high-speed-video analysis of foot-ball impact found impact characteristics influenced impact efficiency, ankle plantarflexion, ball flight characteristics, and kicking accuracy. Increasing ankle joint stiffness, impact locations on the foot closer to the ankle joint, altering foot-ball angle and reducing foot velocity each increased impact efficiency. These results supported the coaching cue ‘maintaining a firm ankle’ during impact as effective at increasing impact efficiency. The impact location between the foot and ball across the medial-lateral direction, foot-ball angle and foot trajectory were each identified as influential to ball flight characteristics and/ or kicking accuracy. The oblique impact theory applied to the duration of impact provided a theoretical framework underpinning how each impact characteristic influenced ball flight characteristics. More consistent performing players produced less kick-to-kick variability in their impact characteristics, while lower kick accuracy was due to errors produced in the combination of impact characteristics. In conclusion, foot-ball impact characteristics were influential to impact efficiency, ankle plantarflexion, ball flight characteristics, and kicking accuracy.

For women in Colombia playing sports was taboo for years. However, through Sport for Development and Peace (SDP) organizations, new spaces for female participation have emerged in recent decades. My research questions how girls and young women’s participation in a Colombian SDP organization shapes and constrains gender relations. This research includes six months of ethnographic fieldwork. Sixty interviews and many observations of participant's engagement were conducted in two distinct, low socio-economic neighborhoods where the SDP organization operates. My findings show female SDP participants are challenging gender roles in Colombia. The challenges were done in subtle and sometimes more overt ways with varying degrees of success; often rife with tensions and contradictions. Drawing from a decolonial feminist perspective and using an intersectional/entangled approach, this thesis explores the processes and mechanisms – gendered socialization, accessing alternative femininity, a constrained social bubble – that delimit girls and young women’s participation and perhaps invalidate steps toward social transformation. I argue that although more girls and young women are participating in masculine labeled pursuits, there are critical limitations to social change and female participants demonstrate the coloniality of gender in action. This research offers an in-depth focus on some of the complex and contradictory workings of gender within a sporting context, in Colombia. It also broadly raises some pressing concerns for scholars of gender and sport. Specifically, it calls for more researchers to apply a decolonial approach and for the SDP industry to be decolonized.

This thesis examined the role that task constraints play in promoting transfer of perceptual skill in sport tasks (futsal and soccer). Transfer of learning is the process of adapting a learned behaviour to a new context. Transfer occurs due to the similarity between a learned behaviour and the behaviour required to achieve the task goal. The similarity of information that guides action between the learning and criterion (transfer) tasks facilitates the transfer process. An individual’s ability to perceive information that specifies opportunities for action (affordances), which underpins skilled performance, has been shown to transfer between similar sport tasks. However, it is unknown how task constraints (e.g., rules, equipment and task goal) influence the development and transfer of perceptual skill between similar tasks. While previous research has been limited to examining acute effects, this thesis showed that practicing a sport skill (i.e., passing) for more than 1000 hours using domain-specific task constraints affected how individuals oriented their attention to perceive affordances. These differences in perceptual behaviour influenced how participants transferred their skill to a new context. Learning the passing skill with shorter time to act and in a smaller space (using futsal constraints) promoted a higher magnitude of transfer to a task with longer time and larger space (soccer constraints) than vice versa. Furthermore, the results indicated that learning the passing skill with a modified equipment (futsal ball) positively transferred to the standard equipment (soccer ball). The modified equipment fast-tracked the participants’ ability to perceive information that specified task-relevant affordances, which, in turn, expedited learning. Overall, this thesis extended current knowledge on the role of task constraints in promoting the development and transfer of perceptual skill. Practitioners are encouraged to manipulate task constraints to facilitate the emergence of functional behaviours that transfer to competition.

This thesis investigated the role respiratory muscle work has on locomotor and respiratory muscle oxygen (O2) utilisation during multiple sprint work. To measure O2 delivery and uptake in real time, near-infrared spectroscopy (NIRS) can be used. However, there are inconsistent methods of smoothing and determining peaks and nadirs from the NIRS signal. Therefore, the aim of study 1 was to examine the effects of different methodologies commonly used in the literature on the determination of peaks and nadirs in the vastus lateralis deoxyhaemoglobin (HHbVL) signal. Means derived from predetermined windows, irrespective of length and data smoothing, underestimated the magnitude of peak and nadir [HHbVL] compared to a rolling mean approach. Based on the results, we suggest using a digital filter to smooth NIRS data, rather than an arithmetic mean, and a rolling approach to determine peaks and nadirs for accurate interpretation of muscle oxygenation trends. In the second study, the effects of heightened inspiratory muscle work on [HHbVL] and respiratory muscle deoxyhaemoglobin ([HHbRM]) trends were examined. In response to the heightened inspiratory muscle work, HHbRM was elevated across the sprint series. There were no clear differences in HHbVL trends between exercise conditions. The lack of difference in HHbVL between trials implies respiratory muscle O2 uptake does not limit locomotor oxygenation trends. Study 3 investigated the role of arterial hypoxemia on respiratory muscle oxygenation trends, and its implications on locomotor oxygenation. While exercising in hypoxia (14.5% O2), HHbVL was higher during the sprint and recovery phases of the repeated-sprint protocol compared to normoxia (21% O2). There were no clear differences in respiratory muscle oxygenation trends between conditions. The clear reduction in locomotor muscle O2 delivery (inferred from HHbVL) while respiratory muscle oxygenation was maintained, suggests preferential blood flow distribution to the respiratory muscle to compensate for arterial hypoxemia, which may explain in part compromise locomotor O2 delivery. The aim of the final study was to examine the role of respiratory muscle strength on locomotor and respiratory muscle oxygenation trends in repeated-sprint exercise. Inspiratory muscle training (IMT) was used to reduce the relative intensity of exercise hyperpnoea by strengthening the respiratory muscles. Repeat-sprint ability was again assessed in normoxia and hypoxia. After 4 weeks of training, there was a 35% increase of inspiratory muscle pressure in the IMT beyond the control group. Despite the substantial change in respiratory muscle strength, oxygenation trends were not affected in either normoxia or hypoxia. The findings of this thesis do not support the work of breathing as being a limiting factor in locomotor muscle oxygenation in normoxia. The intermittent nature of repeated-sprint activity is likely a key mediating factor for which O2 delivery can be maintained to both the locomotor and respiratory muscles. However, under conditions of arterial hypoxemia, locomotor muscle oxygenation may be compromised by preferential O2 delivery to the respiratory muscles.

Training is the systematic application of stress and recovery. The process of striking a balance between stress and recovery is facilitated by monitoring the stress dose (training load) and the response to the applied stress. This thesis investigated several musculoskeletal adaptions in response to training as well as the individual and combined effects of several athlete-monitoring-derived factors on the risk of injury in elite Australian footballers. The first study evaluated the influence of individual internal and external training load and leg dominance on changes in the Achilles and patellar tendon structure. The internal structure of the Achilles and patellar tendons of both lower limbs of 26 elite Australian footballers was assessed using ultrasound tissue characterization at the beginning and the end of an 18 week pre-season. Possibly to very likely small increases in the proportion of aligned and intact tendon bundles occurred in the dominant Achilles (initial value 81.1%; change, ±90% confidence limits 1.6%, ±1.0%), non-dominant Achilles (80.8%; 0.9%, ±1.0%), dominant patellar (75.8%; 1.5%, ±1.5%), and non-dominant patellar (76.8%; 2.7%, ±1.4%) tendons. Measures of training load had inconsistent effects on changes in tendon structure; for example, there were possibly to likely small positive effects on the structure of the non-dominant Achilles tendon, likely small negative effects on the dominant Achilles tendon, and predominantly no clear effects on the patellar tendons. The small and inconsistent effects of training load are indicative of the role of recovery between tendon overloading (training) sessions and the multivariate nature of the tendon response to load with leg dominance a possible influencing factor. The aim of the second study was to determine the normal week-to-week variability of the sit and reach test (S&R), dorsiflexion lunge test (DLT), and adductor squeeze test (AST) scores, as well as the individual differences in variability and the effects of training load on the scores. Forty-four elite Australian rules footballers completed the weekly musculoskeletal screening tests on day two or three post-main training (pre-season) or post-match (in-season) over a 10 month season. Ratings of perceived exertion and session duration for all training sessions were used to derive various measures of training load via both simple summations and exponentially weighted moving averages. Data were analysed via linear and quadratic mixed modelling and interpreted using magnitude-based inference. Substantial small to moderate variability was found for the tests at both season phases; for example over the in-season, the normal variability ±90% confidence limits were as follows: S&R ±1.01 cm, ±0.12; DLT ±0.48 cm, ±0.06; AST ±7.4%, ±0.6%. Small individual differences in variability existed for the S&R and AST (factor standard deviations between 1.31 and 1.66). All measures of training load had trivial effects on the screening scores. A change in a test score larger than the normal variability is required to be considered a true change. Athlete monitoring and flagging systems need to account for the individual differences in variability. The S&R, DLT, and AST are not sensitive to internal training load when conducted two or three days post-training or post-match, and the scores should be interpreted cautiously when used as measures of recovery. Study three evaluated the individual and combined effects of several athlete-monitoring-derived factors on the risk of soft-tissue non-contact injuries. A cohort of 55 elite Australian footballers was prospectively monitored over two consecutive seasons. Internal and external training load was quantified using the session rating of perceived exertion and GPS/accelerometer units, respectively. Cumulative loads and acute-to-chronic workload ratios were derived using rolling averages and exponentially weighted moving averages (smoothed loads). History of injuries in the current and previous seasons was also recorded along with professional experience, weekly musculoskeletal screening, and subjective wellness scores for individual athletes. Individual and combined effects of these variables on the risk of injury were evaluated with generalized linear mixed models. High cumulative loads and acute-to-chronic workload ratios were associated with increased risk of injuries. The effects for measures derived using exponentially weighted moving averages were greater than those for rolling averages. History of a recent injury, long-term experience at professional level, and substantial reductions in a selection of musculoskeletal screening and subjective wellness scores were also associated with increased risk. The effects of high cumulative load were underestimated by ~20% before adjusting for previous injuries, whereas the effects of high acute-to-chronic workload ratios were overestimated by 10-15%. Injury-prone players were at a more than five times higher risk of injuries compared to robust players (hazard ratio 5.4, 90% confidence limits 3.6–12). Combinations of multiple risk factors were associated with extremely large increases in risk; for example, a hazard ratio of 22 (9.7–52) was observed for the combination of high acute load, recent history of a leg injury, and a substantial reduction in the adductor squeeze test score. This study determined that the information from athlete monitoring practices should be interpreted collectively and used as a part of the injury prevention decision-making process along with consideration of individual differences in risk. The findings of this thesis highlight the multivariate nature of the response to training and injuries. This thesis has provided a framework for the monitoring of team sport athletes to ensure a better application of training stress and reduce the now much better understood risk of injury.

Super Rugby is an international competition played in the southern hemisphere with participating teams required to undertake multiple travel during a season. This thesis investigated the direct and complex relationship between regular air travel and athletes’ psycho-physiological response and performance. The first two studies investigated the impact of travel on team performance during the first 21 years of the competition (1996-2006). Study 1 showed the predominant role of the away-match disadvantage in determine match results following the longest flights and greatest time zones shifts, whilst the results from study 2 suggests that fatigue related to long-haul travel and the increased physical demand of the game negatively impacted team performance measured using Key Performance Indicators. Study 3 was a socio-physiological analysis of all travel related issues and solutions, as reported by travel managers from eight Super Rugby teams. The results show that psychological and emotional well-being may take primacy over physiological wellness as team culture and cohesion may be as important as biological interventions in controlling the negative effects of travel on players’ performance and well-being. Studies 4 and 5 monitored players from four teams and investigated their individual response to long-haul trans-meridian travel, with a focus on sleep (study 4), wellness and performance (study 5). The results suggest that, although the effects of travel on individual performance appear to be limited, long-haul travel had a substantially negative impact on players’ sleep and wellness. Further studies should investigate the potential impact of sleep disruptions and reduced wellness on players’ general health and well-being. The findings of this thesis should be of interest to all coaches and supporting staff in sports that require international travel to compete.

Few studies have examined the extent to which mentoring and networking supports have assisted women in developing their careers in male dominated sport organisations where men have traditionally held the reins of power. This current study explores the value of mentoring and networking from a woman‟s perspective in senior and middle management positions at the Australian Football League (AFL). Research has revealed many personal, career and social challenges faced by women employed in management positions, particularly where men dominate the organisations‟ operations (Coleman, 2011; Sturges, 1999; Cha, 2013; Bierema, 2005; Heilman, 2012; Linehan, Scullion & Walsh, 2001). Research for this current study comprised semi-structured interviews with 19 women in senior and middle management positions in the AFL. The data was used to determine the effectiveness and impact of mentoring and networking on career development of women managers in a sports organisation. Data was coded manually and using computer assisted qualitative data analysis software (CAQDAS). The CAQDAS software program used as part of this research was NVivo. The manual and CAQDAS helped to identify key nodes and sub-nodes. Results revealed that when mentoring was well structured and ongoing, it enabled participants to not only appreciate the organisation‟s formal authority relations and communication structures, it also assisted in developing an awareness of its operating culture, informal networks and power relations. Results also revealed networking was unavoidable and came with a wide range of benefits. Findings from this current study expanded knowledge on social capital theory and have the potential to enhance existing, and shape new formal mentoring programs incorporated at the AFL.

Life histories of many famous Australian Rules football figures have been published. Yet despite John ‘Sam’ Newman having a significant influence as both a player and a media persona, neither aspects of his career have been the focus of systematic academic study. This thesis aims to redress the deficiency by deploying biographical methods to examine both Newman’s football and media careers. The first half of the thesis explores how a privileged secondary education shaped Newman’s attitude to life and football, before turning to his football career with the Geelong Football Club. The second half of the thesis traces Newman’s increasingly controversial media career in print, radio, and television – most notably on Channel Nine’s The Footy Show. A key aim of the thesis is to explore how and why the warm and generous John Newman developed the outlandish, sexist, patronising, opinionated, and narcissistic, persona of ‘Sam’ Newman that has both attracted and appalled television audiences for decades. Accordingly, the thesis concludes that Newman is a complex person, exhibiting two different personalities that sometimes coalesce, thus filling an intriguing gap in the corpus of studies of the playing and media careers of influential Australian Rules footballers.

Global populations are ageing, and people need to be physically active for good health. Research about physical activity for older adults has focused on general physical activity rather than community sport. This research investigated the benefits of, and barriers to, community sport participation for older adults and for sporting organisations trying to engage older adults. Reasons for older adult drop out and re-engagement in sport, and potential modifications to attract and/or retain older adults were also investigated. This research utilised the Socio-Ecological model, Capacity Building strategies, Leisure Constraints and Organisational Change theories. An exploratory sequential mixed method approach was utilised, comprising of two studies. Study 1 involved eight focus groups (n=49) with representatives from two Australian National Sporting Organisations (NSOs), older adult sport club members and non-members. Study 2 was an online survey to Australian NSOs and State Sporting Organisations (n=171). The prominent benefit for older adults participating in sport were health and the most discussed barrier to participation was lack of appropriate playing opportunities. The main organisational benefits were to increase participation numbers and volunteering capacity, whilst the main organisational barrier was a focus on youth. The main reason for drop out was a lack of age appropriate opportunities, whilst older adults can re-engage with sport when their families played. Modifications to attract and/or retain older adults included changing the way sport was advertised and partnering with external organisations. There is a clear nexus between the main results and sport policy, with a lack of priority for older adults and therefore low sport participation. A re-orientation of sport policy is required to allow sporting organisations to focus strategically on older adults. With an ageing population and the pressure for sport to increase their participation numbers, older adults are an ideal market. There is also an opportunity to further highlight the social, mental and physical health opportunities that sport offers, especially for older adults.

Tennis at the elite level is a sport that is intermittent in nature and requires proficiency across a number of key performance attributes; physical, technical, tactical and psychological (Fernandez-Fernandez, Sanz-Rivas, & Mendez-Villanueva, 2009; Hornery, Farrow, Mujika, & Young, 2007a; Kovacs, 2006, 2007; Unierzyski, 2002). The diverse skill set required for success in tennis poses a problem for practitioners attempting to identify and develop talent at an early age. The current methods of talent identification in tennis are largely based on ranking and tournament results despite reported low success rates (Brouwers, De Bosscher, & Sotiriadou, 2012). These methods represent an evaluation of current performance, often overlooking the capacity for further development, which is essential in any talent identification/development program (Martindale, Collins, & Daubney, 2005). Movement and skill adaptability (used interchangeably with the term adaptability herein) is an individual’s ability to acutely adjust their performance based on the changing constraints within the performance environment (Martin, Nejad, Colmar, & Liem, 2012; Newell, 1986). This definition has merit for use in tennis as optimal performance requires a player must be able to acutely modify their game in relation to the changing stimuli. Adaptability is relevant for talent identification purposes as it is representative of the dynamic, unpredictable nature of the sporting environment. To progress from a theoretical concept, development of adaptability metrics is required combined with evidence of its impact as a training mechanism. Therefore, two novel measures of adaptability; the throwing and rebound task (TRT) and the continuous rebounding task (CRT) were created. Construct and face validity of both tasks was established, as was reliability via a test-retest method. Adaptability explained a higher percentage of tennis performance (assessed via a volley test), when compared to anthropometric, maturation, physical performance and general motor skill variables. This demonstrates the importance of adaptability in junior tennis performance. In contrast to the volley test, coaches’ subjective stroke evaluation reported no significant relationships. Adaptability was compared to a conventional tennis training program, with both groups reporting significant improvement on a number of variables (best TRT, average TRT, sum CRT, KörperKoordinations Test Für Kinder [KTK] and forehand stroke evaluation). Importantly, only the adaptability group improved on a timed, tennis-specific accuracy task and reported higher levels of enjoyment than the conventional tennis training group. These findings provide evidence for potential inclusion of the TRT and CRT into tennis talent identification programs. Additionally, the importance of adaptability as a theoretical construct which can develop junior players has been established. More broadly, the theoretical concepts underpinning adaptability as a testing mechanism (TRT and CRT) and training method could be applied to other sports where time constrained perception-action is required.

Women’s soccer in Australia has historically been met with hostility. The Australian national women’s team is more accomplished than their male counterparts in terms of performance outcomes, yet they continue to experience considerably lower financial support and inferior media focus. At the same time more girls are playing soccer compared to netball, traditionally the most popular sport for girls. Women-only soccer clubs and teams have in part facilitated the growth of women’s soccer as they encourage girls and women to participate (and stay) in soccer because (as many feminist scholars have stated) women-only spaces allow the embedded power inequalities that exist within hegemonic masculine spaces to be overcome. This research aimed to gain a deeper understanding of 'female empowerment' by exploring the politics and structure of a women-only soccer club, and the lived experiences of its members. Stemming from my extensive involvement in and experience playing soccer I employed an ethnographic methodology to carry out the research. I spent two seasons 'in the field' as a player and committee member at a women-only soccer club in Melbourne conducting observations and life-history interviews. The findings reveal how the soccer players negotiate gender and the different ways in which they are, or feel, empowered through belonging to the club. The thesis contributes to the broader sociological literature on female sport and highlights the politics and paradoxes of sex-segregated sport.

Overview. Neuromuscular fatigue is defined as a reversible exercise-induced reduction in the ability to produce maximal voluntary force or power, originating from central (upper and lower motoneurons) and peripheral (skeletal muscle) sources. It is a symptom that can reduce exercise performance, diminish quality of life, and impair activities of daily living across a wide range of populations. In the lower-limb, the knee extensor muscles are of particular importance as they largely contribute to the execution of functional motor tasks (e.g. locomotion, sit to stand, climbing stairs). Therefore, fatigue of this muscle group is likely to have a large negative impact on the ability of the lower-limbs to generate power. General methodology. Within this thesis, a series of three experiments were conducted to investigate the effect of neuromuscular fatigue in the knee extensor muscles on lower-limb power production. Neuromuscular fatigue of the knee extensor muscles was assessed via changes in isometric maximal voluntary force (IMVF), voluntary activation (VA), maximal evoked resting twitch forces (RT), maximal muscle compound action potentials (M-wave) and voluntary surface electromyography (EMG) amplitude normalized to M-wave (EMG.M-wave-1). Lower-limb power production was measured on a stationary cycle ergometer. Motor command was investigated during cycling exercises via changes in: EMG activity of individual lower-limb muscles [vastus lateralis and vastus medialis (VAS), rectus femoris (RF), gluteus maximus (GMAX), biceps femoris and semitendinosus (hamstrings: HAM), medial and lateral gastrocnemius (GAS) and soleus (SOL) (ankle plantar flexors: APF) and tibialis anterior (TA)]; co-activation indices (CAI) of various muscle pairs [VAS/APF, VAS/HAM, GMAX,RF, GMAX/APF]; and muscle activation variability via the variance ratio (VR). Chapter 3 - study one. Introduction: Neuromuscular fatigue of the knee extensors develops during prolonged high-intensity submaximal exercise and is thought to limit lower-limb power production during subsequent maximal exercise. Aims: The first aim was to investigate the association between changes in EMG activity of VAS muscles during prolonged high intensity cycling exercise and the development of knee extensor fatigue. The second aim was to investigate the effect of knee extensor fatigue developed during prolonged high intensity cycling exercise on lower-limb power production and movement control during a subsequent maximal 30-s cycling exercise. Method: Seven physically active participants volunteered for the study. On one day, a maximal 30-s cycling exercise was completed. On the second day, a maximal 30-s cycling exercise was completed after 10-min of high-intensity cycling. Results: Over the course of high-intensity cycling, VAS EMG and GMAX/RF co-activation increased (P ≤ 0.05). The increase in VAS EMG (range from 6% to 14%) was negatively correlated with the reduction in IMVF following high-intensity exercise (from -2% to -36%; r = 0.791, P ≤ 0.05). During the 30-s maximal effort completed following high-intensity cycling, a positive correlation (r = 0.757, P ≤ 0.05) was seen between changes in IMVF and the changes in maximal lower-limb power production (from 0% to -27%). EMG reduced for all muscles, especially GMAX (-21 ± 8%) and VAS (-16 ± 13%) (P ≤ 0.05). Co-activation reduced for GMAX/RF and VAS/HAM (both P ≤ 0.05), but did not change for VAS/GAS (P > 0.05). Discussion: Larger increases in VAS EMG during prolonged high-intensity cycling exercise were associated with greater levels of knee extensor fatigue, which subsequently decreased maximal power generated by the lower-limbs. The increase in co-activation for GMAX/RF during high intensity exercise and maintained co-activation for VAS/GAS during maximal exercise, suggests that movement control was adjusted to limit fatigue occurrence in the knee extensor muscles and to maximise lower-limb power production. Conclusion: Knee extensor fatigue developed during prolonged high-intensity exercise decreases maximal lower-limb power production during subsequent maximal exercise. Chapter 4 - study two. Introduction: Fatigue is likely to accumulate in the lower-limb muscles during cycling exercises, making it difficult to isolate the effect of knee extensor fatigue on power production. Knee extensor fatigue may also induce movement variability and effect maximal activation of other lower-limb muscles. Aims: The first aim was to investigate if the level of fatigue induced by a pre-fatiguing knee extension exercise determines the level of reduction in power output during the extension and flexion phases of maximal cycling exercise. The second aim was to investigate how motor command during maximal cycling is affected by pre-fatigue of the knee extensors. Method: Ten physically active participants volunteered for this study. On one day, participants completed a 30-s maximal cycling exercise. On the second day, the same participants completed a 30-s maximal cycling exercise following a pre-fatiguing bilateral knee extension exercise. Results: Pre-fatiguing knee extension exercise decreased IMVF by -52 ± 23% (P ≤ 0.05). No association was reported between reductions in knee extensor IMVF following pre-fatiguing exercise (range = -18% to -82%, P ≤ 0.05) and reductions in leg extension power during maximal cycling (range = -8% to -31%, P ≤ 0.05) (r = 0.19). Large reductions were observed for VAS EMG (-15%) GMAX EMG (-12%) and VAS/APF co-activation (-15%) (all P ≤ 0.05). For the primary flexion phase muscles, large reductions were observed for HAM EMG (-15%), TA EMG (-15%) and RF EMG (-11%) (all P ≤ 0.05). Inter-individual variability increased for all crank forces and EMG activity for VAS, RF, HAM and TA (all P ≤ 0.05). Discussion: Overall, the results indicate that knee extensor fatigue developed during pre-fatiguing exercise does not determine reductions in power output during maximal cycling exercise. Alterations in motor command likely explain this result, evidenced via large reductions in EMG of local and non-local muscles, and increased inter-individual variability in crank forces and muscle activation patterns. Conclusion: The level of isolated fatigue observed in the knee extensors does not determine the level of reduction in leg extension power during maximal cycling exercises, presumably due to increased movement variability. Chapter 5 - study three. Introduction: Reducing the complexity of the cycling movement to a unilateral leg extension exercise would potentially reduce the degree of freedom and decrease variability in motor command. In this way, it is possible that knee extensor fatigue would determine the reduction in power output during the extension phase of maximal cycling. Knee extensor fatigue measurements are typically obtained post-exercise and within a time delay of 40-s to 5-min, although it remains unknown if such assessments provide an accurate measure of knee extensor fatigue developed during cycling exercise. Aims: The first aim was to compare the rate of fatigue occurrence in the knee extensors between an isolated knee extension exercise and a modified cycling exercise consisting of the leg extension phase only. The second aim was to investigate any differences in knee extensor fatigue measured post-exercise and the maximum time delays for which fatigue responses could be accurately assessed. Method: On separate days, 16 physically active participants completed 60 maximal knee extensions on an isokinetic dynamometer or 60 maximal leg extensions on an isokinetic cycle ergometer. A mechanical goniometer verified identical knee joint range of motion (~ 120° - 30° flexion, 0° = full extension) and angular velocity (~80°.s-1). Electrical stimulation of the femoral nerve was automated during exercise at a consistent knee joint angle of 90°. Average measures of maximal torque, M-wave and VAS EMG.M-wave-1 were calculated at the iv start (contraction 2 - 4), middle (contraction 29 - 31) and end (contraction 58-60). IMVF, VA, RT100 HZ and RT10:100 HZ were measured pre-exercise, and again at 5-s, 20-s, 40-s, 1-min, 1.5-min, 2-min, 3-min, 4-min and 5-min post-exercise Results: Intra-individual reductions in maximal torque during knee extension were positively correlated to torque reduction during leg extension exercise at the middle (-45 ± 11% vs. -23 ± 12%, r = 0.79, P ≤ 0.05) and end (-59 ± 10% vs. -37 ± 13%, r = 0.86, P ≤ 0.05). Greater reductions during knee extension were shown for RF EMG (middle: -17 ± 15% vs -2 ± 20%; end: -34 ± 16% vs. -4 ± 22%) and VAS EMG.M-wave-1 (end: -21 ± 16% vs. -14 ± 17%) (all P ≤ 0.05). IMVF reduction measured 5-s post knee extension (-32 ± 12%) partially recovered within 2-min (P > 0.05), whereas the reduction in RT100 (-28 ± 18%) and RT10:100 (-17 ± 15%) partially recovered within 20-s and 40-s, respectively (P > 0.05). Discussion: The level of fatigue developed in the knee extensors determines the reduction in maximal torque during leg extension exercise. This is likely due to the removal of the leg flexion phase and contribution of the contralateral leg during exercise. The longest time delay for accurate assessment of isometric maximal voluntary force of the knee extensors post-exercise was 1.5-min. To avoid underestimating high and low frequency peripheral fatigue, assessment must be conducted within less than 20-s and 40-s post-exercise, whereas reductions in central fatigue measurements were greatest between 20-s and 2-min post-exercise. Conclusion: Fatigue resistance in the knee extensors may predict the ability to maintain high levels of power during the extension phase of maximal cycling. Summary: Study one revealed that VAS EMG increase during high-intensity cycling exercise (6% to 14%) is associated to IMVF decrease (-2% to -36%), and that IMVF decrease is associated to reductions in maximal lower-limb power (0% to -27%) (r = 0.76). However, fatigue development was likely in other lower-limb muscles during high-intensity cycling, making it difficult to isolate the effects of knee extensor fatigue on lower-limb power production. Therefore, study two sought to isolate fatigue in the knee extensors prior to a maximal cycling effort, with the results from this study revealing no clear association between an isolated reduction in knee extensor IMVF (-18% to -82%) and reductions in maximal leg extension power (-8% to -31%) (r = 0.1), presumably due to alterations in movement control. Study three aimed compare the rate of fatigue occurrence in the knee extensors between an isolated knee extension exercise and a modified cycling exercise consisting of the leg extension phase only. The novel finding from this study was that torque reduction during knee extension was strongly associated to torque reduction v during leg extension from the start to middle (r = 0.79), middle to end (r = 0.67) and start to end periods of the exercise (r = 0.86). The results also highlighted the need to assess peripheral muscle fatigue within 20-s post-exercise, and isometric force within 1.5-min post-exercise, if accurate measures of the exercise-induced changes are to be obtained. Practical implications and importance: Collectively, the results from all studies suggest that individuals with a greater capacity to resist fatigue development in their knee extensors may have a greater capacity to maintain high levels of power during maximal cycling exercises. However, severe levels of knee extensor fatigue may lead some individuals to adopt a wider range of movement strategies to generate crank power. This information may be used by sport scientists and coaches to improve exercise prescription and performance outcomes.

This thesis explores how volunteers within community sports clubs engage with diversity work, in the form of intellectual disability. Volunteers are the central spine to many sports clubs in western societies and the delivery of sporting provision is placed upon them. They are further faced with growing ambitions in delivering an array of social outcomes such as social and cultural diversity. The capacity of voluntary sports clubs to deliver such ambitious agendas is contested. This thesis argues that volunteers do not see their job as doing diversity work, specifically in the form of intellectual disability. This is because many community sports clubs value able-bodied performance and winning, and view their core business as fielding teams for competition. This thesis presents findings from a ten-month ethnographic study to explore how volunteers in one community sports club in Melbourne, Australia, engaged with diversity work by fielding two cricket teams for athletes with an intellectual disability. I drew upon diversity management literature and Sara Ahmed’s (2006; 2006b; 2007a; 2007b; 2008; 2009; 2012; 2017) numerous studies on diversity work in institutional life as the basis for my conceptual framework. The results showed that only a few select volunteers at the club engaged in diversity work by volunteering with two specialist teams for athletes with an intellectual disability. These teams were referred to as the ‘All Abilities’ teams. Further, volunteers committed to promoting diversity at the club met various forms of resistance within the club. The capacity to address diversity issues was influenced by the attitudes of key volunteers within the club and the availability of volunteers willing to engage in diversity work. Volunteers committed to implementing diversity policies and programs reported feeling unsupported, overburdened and, at times, burned out. The thesis concludes with practical recommendations and considerations for community sports volunteers in delivering diversity efforts around intellectual disability.

This study systematically explored the outcomes and implementation processes of the School Sport Leadership Program (SSLP), which was integrated into some secondary schools in Melbourne, Australia. The main principle behind the SSLP was to train secondary school-aged students to become sport leaders, who deliver sporting activities to primary schools with the aim to encourage participation in sports and physical activities and develop their competencies. The overarching aim of this research was to evaluate the impact of the program utilising rigour methodology design, and to provide a comprehensive view of the developmental outcomes for the young people, as well as the program’s impact on the school community.

Aerobic fitness and repeated high-intensity efforts have been shown to be a determinant in the performance of team sports, especially in the ability to finish a match, to cover a distance, to repeat and recover between sprints and explosive movements (e.g. accelerations, changes of direction; COD) and to reduce the deterioration in some technical skill. Due to this, coaches must appropriately develop these capacities to adequately prepare athletes for match-play demands. High-intensity interval training is considered an effective and time efficient means to optimise individual physiological adaptation. However, the best processes which examine these qualities (physical testing protocols), prescribe training and monitor the response of this training requires attention, particularly in team sport athletes that possess heterogenous physical attributes. Therefore, this thesis aimed to examine a valid and reliable approach to assess the training outcome as well as prescribe and monitor the training process in rugby league athletes.

Mitochondrial adaptation in skeletal muscle is promoted by a diverse array of stimuli, and changes in mitochondrial plasticity have been noted as a result of a many exercise modalities. High-intensity interval training is one such modality that promotes mitochondrial adaptation in response to repeated short-duration bouts of intense effort. Another result of intense muscular effort is a decrease in muscle pH, resulting in intracellular acidosis. The effect of this acidosis on oxygen consumption in muscle has received attention previously, with mixed findings. An aspect of skeletal muscle mitochondrial function that has received limited attention is the production of reactive oxygen species. To date a small number of studies have also provided evidence that attenuating the development of intracellular acidosis may have beneficial effects for mitochondrial adaptation. This thesis aimed to further investigate the effect of acidosis on mitochondrial function, and on intracellular signalling for mitochondrial biogenesis.

Falls and related injuries are the leading cause of mortality and morbidity in people aged 65 years and older. Despite all the many health benefits already reported from regular exercise participation including reduction of falls, this population group is still reported to be inadequately physically active. Therefore, it is critical to develop and validate new options that can enhance exercise uptake, sustain participation of this group and reduce their risk of having falls.

Attempts have been made to understand the complex dynamic relationships involved in team sports and explain the nature of successful performance. In sports, these components are particularly relevant because athletes often attribute peak performances and outcomes to psychological states such as team flow. This thesis focused on exploring team flow state as an independent construct whose dimensions need to be identified by research. The purpose of this thesis was to conceptualize team flow state and develop an inventory to measure it.

...the aim of this research was to investigate if maternal exercise (Chapter 3) or offspring early in life exercise (Chapter 4) could attenuate the negative metabolic consequences in adult rat offspring sired by high-fat fed obese fathers (Chapter 3 and 4).