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The purpose of this study was to introduce a continuous quality improvement (CQI) program for radiation dose optimisation during uterine artery embolisation (UAE) and assess its impact on dose reduction and image quality. The CQI program investigated the effects of optimising radiation dose parameters on the kerma-area product (KAP) and image quality when comparing a ‘CQI intervention’ group (n = 50) and ‘Control’ group (n = 50). Visual grading characteristics (VGC) analysis was used to assess image quality, using the ‘Control’ group as a reference. A significant reduction in KAP by 17% (P = 0.041, d = 0.2) and reference air kerma (Ka, r) by 20% (P = 0.027, d = 0.2) was shown between the two groups. The VGC analysis resulted in an area under the VGC curve (AUCVGC) of 0.54, indicating no significant difference in image quality between the two groups (P = 0.670). The implementation of the CQI program and optimisation of radiation dose parameters improved the UAE radiation dose practices at our centre. The dose reduction demonstrated no detrimental effects on image quality.

Purpose: The study aimed to (1) accurately examine longitudinal relationships between maturity status and both technical skill indices and performance in Australian male (N = 64) age-group Front-crawl swimmers (10–15 y) and (2) determine whether individual differences in maturation influenced relationships between technical skill level and swimming performance. Methods: A repeated-measures design was used to assess maturity status and performance on 200-m Front-crawl trial across 2 competition seasons (2018–2020). Assessments were made on 3 to 5 occasions (median = 3) separated by approximately 4 months. Average horizontal velocity and stroke frequency were used to calculate technical skill indices, specifically stroke index, and arm propelling efficiency. Relationships between variables were assessed using linear mixed models, identifying fixed, and random effect estimates. Results: Curvilinear trends best described significant longitudinal relationships between maturity status with horizontal velocity (F = 10.33 [1, 233.77]; P = .002) and stroke index (F = 5.55 [1, 217.9]; P = .02) during 200-m Front-crawl trials. Maturity status was not significantly related to arm propelling efficiency (P = .08). However, arm propelling efficiency was an independent predictor of Front-crawl velocity (F = 55.89 [1, 210.45]; P Conclusions: Maturity status predicted assessment of swimmer technical skill (stroke index) and swimming performance. However, technical skill accessed via arm propelling efficiency was independent of maturation and was predictive of performance. Maturity status influences performance evaluation based on technical skill and velocity. Findings highlight the need to account for maturation and technical skill in age-group swimmers to better inform swimmer evaluation.

Similar muscle performance adaptations have been shown following volume-equated resistance training using cluster (CLUS) versus traditional (TRAD) set structures. This study aimed to examine the effects of higher-volume CLUS compared to lower-volume TRAD set structures on muscle performance.Twenty resistance-trained males (age 20.9±4.3 years) were randomized into one of two bench press training routines performed for 6 weeks. Subjects in CLUS (N.=10), performed six sets of five repetitions at 85% one-repetition maximum (1RM) with 30 seconds inter-repetition rest and three minutes of inter-set rest. In contrast, subjects in TRAD (N.=10) performed three sets of five repetitions at 85% 1RM with five minutes of inter-set rest. Muscular strength (1RM), concentric velocity, power, local muscular endurance and maintenance of muscle performance (in training sessions) were assessed.For 1RM there was a significant time effect (P0.001) with moderate effect sizes (ES) within each group (CLUS: ES=0.48; TRAD: ES=0.67). A trend towards significant time effect was found for concentric velocity (P=0.05; CLUS: ES=-0.36; TRAD ES=-0.96). There were no other significant time or group effects nor group × time interactions. Greater maintenance of concentric velocity and power (sets 1-3) was found for CLUS compared to TRAD at week one (P0.05) but not at week 6.High load resistance training in the bench press exercise, utilizing intra-set rest periods to increase the training volume, does not yield any muscular performance benefits compared to traditional set structures.

Davies, TB, Halaki, M, Orr, R, Mitchell, L, Helms, ER, Clarke, J, and Hackett, DA. Effect of set structure on upper-body muscular hypertrophy and performance in recreationally trained men and women. J Strength Cond Res XX(X): 000-000, 2021-This study explored the effect of volume-equated traditional-set and cluster-set structures on muscular hypertrophy and performance after high-load resistance training manipulating the bench press exercise. Twenty-one recreationally trained subjects (12 men and 9 women) performed a 3-week familiarization phase and were then randomized into one of two 8-week upper-body and lower-body split programs occurring over 3 and then progressing to 4 sessions per week. Subjects performed 4 sets of 5 repetitions at 85% one repetition maximum (1RM) using a traditional-set structure (TRAD, n = 10), which involved 5 minutes of interset rest only, or a cluster-set structure, which included 30-second inter-repetition rest and 3 minutes of interset rest (CLUS, n = 11). A 1RM bench press, repetitions to failure at 70% 1RM, regional muscle thickness, and dual-energy x-ray absorptiometry were used to estimate changes in muscular strength, local muscular endurance, regional muscular hypertrophy, and body composition, respectively. Velocity loss was assessed using a linear position transducer at the intervention midpoint. TRAD demonstrated a significantly greater velocity loss magnitude (g = 1.50) and muscle thickness of the proximal pectoralis major (g = -0.34) compared with CLUS. There were no significant differences between groups for the remaining outcomes, although a small effect size favoring TRAD was observed for the middle region of the pectoralis major (g = -0.25). It seems that the greater velocity losses during sets observed in traditional-set compared with cluster-set structures may promote superior muscular hypertrophy within specific regions of the pectoralis major in recreationally trained subjects.

Paternal postnatal depression is an emerging public health concern, with negative outcomes for men, their partners, and the newborn. There is a dearth of data on paternal postnatal depression in lower-middle-income countries like Pakistan. This study aimed to identify risk factors of postnatal depression in Pakistani men. Men who consented to this cross-sectional study completed a questionnaire that included sociodemographic information and Urdu translated versions of the Edinburgh Postnatal Depression Scale (EPDS) and the Pittsburgh Sleep Quality Index, 10-12 weeks postpartum. Descriptive analyses for the sociodemographic variables were calculated. Univariate analyses were conducted to calculate the relative risk and 95% confidence interval of the independent variables with an EPDS score of10. Multivariate binary logistic regression models were performed for risk factors of paternal postnatal depression. Fifty-one questionnaires were analyzed and 23.5% of the participants scored more than 10 on the EPDS. Spouse's EPDS score 12, and own sleep disturbance were risk factors of paternal postnatal depression in Pakistani men. There is an imminent need to incorporate fathers in the existing and future perinatal mental health programs in Pakistan.

Abstract Objectives Experimental pain is a commonly used method to draw conclusions about the motor response to clinical musculoskeletal pain. A systematic review was performed to determine if current models of acute experimental pain validly replicate the clinical experience of appendicular musculoskeletal pain with respect to the distribution and quality of pain and the pain response to provocation testing. Methods A structured search of Medline, Scopus and Embase databases was conducted from database inception to August 2020 using the following key terms: “experimental muscle pain” OR “experimental pain” OR “pain induced” OR “induced pain” OR “muscle hyperalgesia“ OR (“Pain model” AND “muscle”). Studies in English were included if investigators induced experimental musculoskeletal pain into a limb (including the sacroiliac joint) in humans, and if they measured and reported the distribution of pain, quality of pain or response to a provocation manoeuvre performed passively or actively. Studies were excluded if they involved prolonged or delayed experimental pain, if temporomandibular, orofacial, lumbar, thoracic or cervical spine pain were investigated, if a full text of the study was not available or if they were systematic reviews. Two investigators independently screened each title and abstract and each full text paper to determine inclusion in the review. Disagreements were resolved by consensus with a third investigator. Results Data from 57 experimental pain studies were included in this review. Forty-six of these studies reported pain distribution, 41 reported pain quality and six detailed the pain response to provocation testing. Hypertonic saline injection was the most common mechanism used to induce pain with 43 studies employing this method. The next most common methods were capsaicin injection (5 studies) and electrical stimulation, injection of acidic solution and ischaemia with three studies each. The distribution of experimental pain was similar to the area of pain reported in clinical appendicular musculoskeletal conditions. The quality of appendicular musculoskeletal pain was not replicated with the affective component of the McGill Pain Questionnaire consistently lower than that typically reported by musculoskeletal pain patients. The response to provocation testing was rarely investigated following experimental pain induction. Based on the limited available data, the increase in pain experienced in clinical populations during provocative maneuvers was not consistently replicated. Conclusions Current acute experimental pain models replicate the distribution but not the quality of chronic clinical appendicular musculoskeletal pain. Limited evidence also indicates that experimentally induced acute pain does not consistently increase with tests known to provoke pain in patients with appendicular musculoskeletal pain. The results of this review question the validity of conclusions drawn from acute experimental pain studies regarding changes in muscle behaviour in response to pain in the clinical setting.

BACKGROUND Longitudinal data investigating tracking of children's lifestyle behaviors and predictors of childhood obesity are limited. OBJECTIVES We examined changes in children's lifestyle behaviors (dietary, physical activity, and screen time) from ages 2-5 y to determine if maternal sociodemographic factors and BMI predict child obesity at 3.5 y and 5 y. METHODS Data were obtained from 667 first-time mothers who were recruited into the Healthy Beginnings Trial at 24-34 weeks of gestation in Sydney, Australia. Child lifestyle behaviors were assessed using face-to-face questionnaire interviews with mothers. To measure child and maternal anthropometry, BMI (in kg/m2) was calculated using measured height and weight. Children were categorized as overweight or obese based on the International Obesity Task Force criteria. We used 1-factor repeated-measures ANOVA to track preschoolers' lifestyle behaviors and multiple logistic regression to determine obesity predictors. RESULTS In children aged 2-5 y, consumption of vegetables (ηp2 = 0.06; P

Introduction Uterine artery embolisation (UAE) is regarded as a safe and effective treatment for symptomatic uterine fibroids and/or adenomyosis. Dose reduction during UAE is critical for this reproductive‐age patient population to minimise the risks of radiation‐induced effects. The aim of this study was to identify the predictors of radiation dose which can be controlled and optimised for patients during UAE. Methods A total of 150 patients between June 2018 and August 2019 were included in this study. Demographic and clinical information such as age, body mass index (BMI), total number of fibroids, total fibroid volume, total uterus volume and dosimetric measurements on Dose Area Product (DAP), Air Kerma (AK) and fluoroscopy time were recorded. Total digital subtraction angiography (DSA), total conventional roadmap (CRM), total last‐image hold (LIH) and total fluoroscopy were calculated from the dose report. Multiple linear regression analysis was used to identify the independent predictor variables of total dose (DAP) using a regression model. Results Total DSA, total CRM and total LIH were identified as the determinants of dose for UAE (P, The predictors of patient radiation dose have been identified for the interventional radiology procedure known as uterine artery embolisation (UAE). A regression model entered and identified total digital subtraction angiography (DSA), total conventional roadmap (CRM) and total last‐image hold (LIH) as the determinants of dose over demographic and other angiographic variables. Control of these dose predictors can potentially minimise radiation dose exposure to this reproductive‐age patient population. Dose optimisation can be attained to reduce the risks of tissue effects and/or stochastic effects associated with irradiating the pelvis region.

Background Acquired brain injury (ABI), such as Parkinson's disease, dementia or stroke, can result in communication difficulties that lead to an impoverished ability to connect meaningfully with others. Choral singing is a complex task that uses multiple brain regions which are also responsible for language and communication skills. The potential therapeutic effects of group singing on communication-related outcomes across ABI aetiologies have not been systematically reviewed. Aims To examine whether participation in group singing over multiple sessions improves speech, voice, language and/or communication skills in individuals with ABI-related communication disorders. Methods & procedures A database search was undertaken according to the PRISMA guidelines. Search terms included: stroke OR Parkinson* OR dementia OR 'acquired brain injury' AND choir OR choral OR singing OR sing OR 'choral sing* ' OR group adj3 singing OR community adj3 singing AND speech OR language OR communication. Main contribution A total of 11 studies were included. Nine were quantitative, including one randomized and one non-randomized control trial, and two were mixed method. Nine studies were scored as level IV (uncontrolled) on the American Academy of Neurology (AAN) Classification of Evidence Matrix and two as level III (e.g., lack of blinded assessors). Eight examined speech and voice skills in Parkinson's disease, two functional communication skills in post-stroke aphasia and one communication between individuals with dementia and a significant other. One level III control trials provided evidence for a therapeutic effect of group singing on communication in individuals with Parkinson's disease. Conclusions & implications Currently, there is only one study providing support for using group singing to improve speech and voice skills in people with Parkinson's disease, and no studies of adequate quality indicating positive effects on language and functional communication abilities in ABI. Further research using more rigorous experimental designs is required to determine whether group singing can influence communication skills in ABI. What this paper adds What is already known on the subject Music activates widespread, bilateral cortical and subcortical brain regions. Group singing is increasingly understood to have positive benefits on quality of life and health-related well-being in both healthy and clinical populations. Given the crossover in neural networks between singing, speech and language, singing activities are also thought to have positive effect of communication impairments secondary to ABI. However, to date, the research evidence supporting the application of group singing for communication impairments in ABI has not been summarized. What this paper adds to existing knowledge A total of 11 studies have looked at communication outcomes after group singing in ABI. For most of these, the quality of evidence was low (AAN level IV). It also highlights that there is a bias in the literature towards the studying individuals with Parkinson's disease (i.e., nine of the 11 studies). What are the potential or actual clinical implications of this work? This review concludes that, currently, there is emerging evidence to support positive effects of a group singing for speech and voice symptoms in individuals with Parkinson's disease, when provided using the Tamplin protocol. However, there is not yet any evidence for communication benefits for individuals with aphasia or dementia.

Introduction It is commonly believed that the shoulder external rotation (ER) to internal rotation (IR) strength ratio is decreased in swimmers due to predominant IR loading during the pull-through (propulsive) phase which predisposes to shoulder pain. However, the evidence supporting this hypothesis is inconclusive. Therefore, the aim of this study was to examine shoulder rotation strength parameters in elite swimmers and investigate potential associations with shoulder pain. Methods Sixty-eight (40 men; age, 19.9 ± 3.2 yr) elite swimmers provided demographic and shoulder pain history data before measurement of shoulder rotation strength. Mixed model analyses were used to examine differences in shoulder IR and ER strength normalized to body weight (BW) and the shoulder rotation strength ratio. A multinomial logistic regression model was utilized to examine associations between shoulder rotation strength parameters and shoulder pain. Results Mean shoulder IR strength (BW) was approximately 0.29 for male swimmers and 0.26 for female swimmers. Mean shoulder ER strength (BW) was approximately 0.19 for male swimmers and 0.18 for female swimmer. The shoulder ER/IR strength ratio was approximately 0.70 bilaterally for all swimmers. There were no significant differences between dominant and nondominant shoulders in IR or ER strength normalized to BW (P ≥ 0.547). There were no associations between any shoulder strength parameters and shoulder pain (r = 0.032, P = 0.107). Conclusions Despite the high IR loading, optimal swimming technique does not alter the normal ER/IR strength ratio at the shoulder. Elite swimmers who report current or a history of shoulder pain demonstrate normal shoulder rotation strength ratios. The finding of symmetrical shoulder rotation strength points to side-to-side strength comparisons as a valuable clinical tool in managing swimmers with unilateral shoulder pain.

The effect of resistance training (RT) on adaptations in muscular strength and hypertrophy has never been examined in an exclusively female synthesis of the literature. The objectives of this study were threefold: (1) to systematically review the literature on female adaptations to RT, characterising the effect in terms of muscular strength and hypertrophy; (2) to distinguish the individual effects of intervention duration, frequency, and intensity on these adaptations via sub-analysis; (3) to draw evidence-based conclusions regarding training expectations in female populations. Three electronic databases were searched using terms related to RT combined with females or women. Random-effects meta-analyses were undertaken to estimate the effect of RT on muscular strength and hypertrophy in females. Possible predictors that may have influenced training-related effects (e.g., training intensity and volume) were explored using univariate analyses. The systematic search identified 14,067 articles of which a total of 24 studies met the inclusion criteria and were eligible. Upper body strength was assessed in 15 studies, lower body strength in 19 studies, and muscular hypertrophy in 15 studies. Study duration lasted between 4 weeks and 12 months. Large-effect sizes were found for upper body strength (Hedges’ g = 1.70; p

Study design Systematic review with meta-analysis. Objective To examine the association between proprioception and pain and disability in people with non-specific low back pain (NSLBP) and the impact of potential moderators on the strength of the association. Summary of background data NSLBP is a common musculoskeletal disorder and a leading cause of disability. Proprioception deficit has been associated with low back pain and correlated with pain and disability; however, the correlation coefficients presented are conflicting. Methods Systematic literature search was performed in eight databases and Google scholar. Two independent reviewers assessed the literature and extracted data. Data of interest included participant characteristics of NSLBP group, pain and disability, proprioception test protocol, and the correlation coefficient between proprioception and pain/disability. Meta-analysis of data from homogeneous studies was performed according to proprioception test methods. Subgroup of movement directions was analyzed. The methodological quality of studies was assessed. Results The literature search identified 3067 records of which 14 studies were included for meta-analysis. Proprioception was measured by active joint repositioning sense (AJRS), passive joint repositioning sense (PJRS), and threshold to detect passive motion (TTDPM). Meta-analysis revealed no significant correlation coefficient between any proprioception measures and pain or disability (P > 0.05). The subgroup analysis showed little correlation between absolute error (AE) of passive lumbar flexion and pain (r = 0.225, 95% CI 0.040-0.395), and between AE of passive lumbar extension and disability (r = 0.196, 95%CI 0.010-0.369). Conclusion AJRS and TTDPM are not correlated with pain and disability in people with NSLBP. The AE of passive lumbar movement is correlated to a small degree with pain and disability. However, the degree of correlation is small and should be interpreted with caution. Therefore, the differences in proprioception observed between people with pain and people without pain seem to be independent of the symptoms. Level of evidence 1.

Purpose: The purpose of this laboratory study was to investigate whether rhythmic speech was primarily responsible for stuttering reductions in four school-aged children after the instatement stage of the Westmead Program of syllable-timed speech (STS) intervention. The study was designed to inform further development of the program. Reduction in variability of vowel duration is a marker of STS, and it was predicted that this would be present in the children's conversational speech after Stage 1 of the program if they were using STS. To strengthen such a finding, it was also predicted that there would be no reduction in articulation rate, sentence complexity, and utterance length after treatment, as there is evidence that reductions in these can reduce stuttering. Perceptual judgments of speech quality after treatment were also made by independent listeners.Method: Participants were four children, ages 8-11 years, who completed Stage 1 of an STS program and whose stuttering had reduced significantly. Pre-treatment (PRE) and post-treatment (POST) within-clinic audio-visual recordings of conversational speech were analysed for percentage of syllables stuttered, variability of vowel duration, articulation rate, and length and complexity of utterance. Four blinded listeners made perceptual judgments of speech quality in the POST recordings.Result: Recordings of all children showed that variability of vowel duration clearly reduced from the PRE to POST speech samples. Importantly, articulation rate and language use were not compromised. Some possible indicators of rhythmicity were identified in one child in the perceptual study.Conclusion: The findings suggest that STS was primarily responsible for the clinically significant reductions in stuttering after Stage 1 of the program. There is an urgent need for more evidence-based interventions for stuttering in this age group and further development of STS interventions is warranted.

Objective To estimate the prevalence and associated risk factors of perinatal depression in Pakistan. Methods We conducted a systematic search of Medline, PsycINFO, CINAHL, EMBASE, and Global health, up through May 31, 2019. Studies reporting on the prevalence of perinatal depression in Pakistan with or without associated risks factors were included. Results Forty-three studies reporting data from 17 544 women met the eligibility criteria and were included. Overall, the pooled prevalence of antenatal depression was 37% (95% CI: 30-44), while that of postnatal depression was 30% (95% CI: 25-36). The prevalence of perinatal depression in women residing in urban areas and those living in rural settings was not significantly different. The most frequently reported risk factors for antenatal depression were intimate partner violence and poor relationship with spouse, and that reported for postnatal depression was low-income level. An unintended pregnancy was significantly associated with perinatal depression in Pakistan. Conclusions We identified variability in prevalence rate of perinatal depression in Pakistan. It is difficult to gauge the true magnitude of this problem potentially due to differing risk factors between the antenatal and postnatal periods and the lack of uniformity of data collection protocols and procedures. The high prevalence rates of 30%-37% compared to global estimates suggest policy makers and stakeholders should direct additional resources toward improving perinatal mental health in Pakistan.

IntroductionProviding effective nutritional rehabilitation to patients hospitalised with anorexia nervosa (AN) is challenging, partly due to conservative recommendations that advocate feeding patients at low energy intakes. An ‘underfeeding syndrome’ can develop when patients are not provided with adequate nutrition during treatment, whereby malnourished patients fail to restore weight in a timely matter, and even lose weight. Of particular concern, the reintroduction of carbohydrate in a starved patient can increase the risk of developing electrolyte, metabolic and organ dysfunction. The proposed trial assesses the efficacy and safety of a lower carbohydrate enteral formula (28% carbohydrate) against a standard enteral formula (54% carbohydrate), in adolescent and young adult patients (aged 15–25 years), hospitalised with AN.Methods and analysisThe study employs a double-blind randomised controlled trial design. At admission to hospital, malnourished adolescent and young adults with AN will be randomly allocated to commence feeding on a standard enteral feeding formula (1.5 kcal/mL, 54% carbohydrate) or a lower carbohydrate isocaloric enteral feeding formula (1.5 kcal/mL, 28% carbohydrate). Assessments of nutritional intake, weight and biochemistry (phosphate, magnesium, potassium) will be conducted at baseline and during the first 3 weeks of hospital admission. The primary outcome measure will be incidence of hypophosphatemia. Secondary outcomes include weight gain, oedema, other electrolyte distortion, length of hospital admission, admission to the Intensive Care Unit (ICU) and number of days to reach medical stability, using defined parameters.Ethics and disseminationThe protocol was approved by the Western Sydney Local Health District Human Research Ethics Committee and institutional research governance approvals were granted. Written informed consent will be sought prior to study enrolment. Study findings will be widely disseminated through peer-reviewed publications and conference presentations.Trial registration numberAustralian New Zealand Clinical Trials Registry (ACTRN12617000342314); Pre-results.

Objectives Conduct a large-scale epidemiological study of injury characteristics (location, type, mechanism, severity, burden) and incidence in community junior rugby league. Design Prospective cohort epidemiology study. Methods Injury surveillance was conducted in three district leagues (Penrith, Canberra, Melbourne) in under 6 (U6) to under 18 years (U18) age groups across the 2016 season. Club sports trainers recorded all match/training medical-attention injuries using a commercial electronic application which recorded injury circumstances and characteristics. Results A total of 13,169 players from 897 teams participated and 408 (89% male) players sustained 485 injuries, 94% of which were match related. The overall injury incidence was 5.9 injuries/1000 player hours and highest in U13–U18 female players (22.2 injuries/1000 player hours). The mean injury severity of 16 ± 31 days missed training/match-play caused an overall injury burden of 94.2 days missed/1000 player hours). Tackles accounted for 84% of injuries. Joint and contusion injuries were the most prevalent injury type and the head (35% total injuries, primarily bruising and bleeding) was the most injured body site. Conclusions This is the first study to report injuries across a large cohort of all-age Australian community junior rugby league players over one season. Injury prevalence was lower than previously reported in junior rugby league suggesting the sport has not become more dangerous for junior players. These findings provide an evidence-base to inform or revise policy, training and injury prevention programs and athlete development pathways in relation to game-wide safety and develop best-practice protocols in injury management for rugby league athlete support personnel.

Context Rugby union is a field-based collision sport with high injury rates. Associations between injury characteristics and global positioning system–derived movement demands in rugby union athletes are yet to be investigated. Objective To investigate associations between match injuries and movement demands, anthropometrics, and physical performance in under-20-years university-level rugby union players. Design Descriptive epidemiology study. Setting Competition season. Patients or Other Participants Rugby union players (n = 34, age = 19.3 ± 0.6 years) from a university club were recruited. Main Outcome Measure(s) Acute medical attention non–time-loss (NTL), medical-attention time-loss (TL), and total medical-attention (MA) injuries sustained were recorded. Principal component (PC) analysis was performed on player-movement demand variables to identify independent-movement demand components. Pearson correlation and bivariate linear regression were used to test associations between match injuries and PCs. Anthropometric and physical performance measures were tested as predictors of match injuries using a forward stepwise multiple regression analysis. Results Backs had lower anthropometric and performance measures than forwards (P < .05), whereas forwards performed fewer weekly movement demands than backs (P < .05). Increases in body mass and skinfold thickness were associated with more injuries (P < .05). Principal component analysis revealed 3 PCs representing overall performance, high-intensity running (HIR) performance, and impacts. Increases in HIR were associated with decreases in NTL upper limb and trunk (r = −0.32, P = .03), NTL musculoskeletal (r = −0.36, P = .05), NTL total (r = −0.46, P < .01), TL musculoskeletal (r = −0.30, P = .05), MA musculoskeletal (r = −0.41, P < .01), and MA total (r = −0.48, P < .01) injuries. Increases in impacts were associated with increased TL (r = 0.32, P = .03) and MA (r = 0.33, P = .03) head or neck injuries. Conclusions Backs experienced greater weekly movement demands than forwards. Increases in HIR demands were associated with decreased acute injuries in university rugby players. Increases in impacts were associated with more acute head or neck injuries. Positional differences in movement demands, anthropometrics, and physical performance highlight the need for position-specific training.

Cummins, CJ, Gray, AJ, Shorter, KA, Halaki, M, and Orr, R. Energetic demands of interchange and full-match rugby league players. J Strength Cond Res 32(12): 3456-3464, 2018-The purpose of this study was to describe and compare the metabolic demands of rugby league for interchange and full-match players in relation to positional groups. Eighteen elite rugby league players were recruited. A time-motion model was used to estimate the energy expenditure and metabolic demands of rugby league match-play using Global Positioning System (GPS) technology. This approach uses players' GPS velocity-time curves to examine running velocity. Players were categorized into positional groups (outside backs, adjustables, wide-running, and hit-up forwards) and then further categorized into full-match or interchange players. Compared with their full-match counterparts, interchange wide-running forwards expended greater energy (43.1 ± 6.1 vs. 28.6 ± 7.5 kJ·kg, p ≤ 0.001, effect size [ES] = -2.38) and produced a higher anaerobic index (p = 0.016, ES = 0.56) and mean power (7.4%, p = 0.003, ES = 0.66) per match. Full-match adjustables expended 94.8% more energy (p ≤ 0.001, ES = -2.3) and performed more moderate accelerations (10.1%, p = 0.014, ES = -0.57) and decelerations (7.6%, p = 0.017, ES = -0.8), than their interchange counterparts. Outside backs did not interchange and hit-up forwards rarely (n = 2) played an entire match. Differing metabolic demands were identified for interchange and full-match players across positional groups, suggesting position-specific conditioning drills are required to model the energetic demands of match-play.

Studies of cerebral haemodynamics have shown changes with increased exercise intensity, but the patterns have been highly variable and reliable associations with cognitive performance have not been identified. The aim of this study was to examine whether exercise-induced changes in oxygenated haemoglobin (O2Hb) led to changes in concomitant cognitive performance. This study examined cardiorespiratory and cerebral haemodynamics during multi-stage exercise from rest to exhaustion, with (Ex + C) and without (Ex) concurrent cognitive performance (Go/No-go task). The presence of the cognitive task affected both cardiorespiratory and cerebral haemodynamics. The patterns in the cerebral haemodynamics during Ex and Ex + C diverged above the respiratory compensation threshold (RCT), but differences were significant only at 100% $$\dot {V}{{\text{O}}_{{\text{2max}}}}$$ , displaying increased deoxygenated haemoglobin (HHb), decreased difference between oxygenated and deoxygenated haemoglobin (HbDiff), and decreased cerebral oxygenation (COx) during Ex + C. More complex haemodynamic trends against intensity during Ex + C suggested that the presence of a cognitive task increases cerebral metabolic demand at high exercise intensities. The levels of O2Hb, HHb, HbDiff and total haemoglobin increased most steeply at intensities around the RCT during both Ex and Ex + C, but these changes were not accompanied by improved cognitive performance. The primary hypothesis, that cognitive performance would match changes in O2Hb, was not supported. Small variations in reaction time and response accuracy across exercise intensities were not significant, suggesting that cognitive performance is unaffected by intense short-duration exercise. Our results add further evidence that exercise-induced changes in cerebral haemodynamics do not affect cognitive performance.

Objectives Electromyographic (EMG) fatigue threshold (EMGFT) is utilised as a correlate of critical power, torque, and force thresholds that establishes a theoretical exercise intensity—the power, torque, or force at which the rate of change of EMG amplitude (ΔE M ¯ G) is zero—below which neuromuscular fatigue is negligible and unpredictable. Recent studies demonstrating neuromuscular fatigue below critical thresholds raise questions about the construct validity of EMGFT. The purpose of this analysis is to evaluate the construct validity of EMGFT by aggregating ΔE M ¯ G and time to task failure (Tlim) data. Design Meta-analysis. Methods Database search of MEDLINE, SPORTDiscus, Web of Science, and Cochrane (inception – September 2016) conducted using terms relevant to EMG and muscle fatigue. Inclusion criteria were studies reporting agonist muscle EMG amplitude data during constant force voluntary isometric contractions taken to task failure. Linear and nonlinear regression models were used to relate ΔE M ¯ G and Tlim data extracted from included studies. Results Regression analyses included data from 837 healthy adults from 43 studies. Relationships between ΔE M ¯ G and Tlim were strong in both nonlinear (R2 = 0.65) and linear (R2 = 0.82) models. ΔE M ¯ G at EMGFT was significantly nonzero overall and in 3 of 5 cohorts in the nonlinear model (p Conclusions EMGFT lacks face validity as currently calculated; models for more precise EMGFT calculation are proposed. A new framework for prediction of task failure using EMG amplitude data alone is presented. The ΔE M ¯ G vs. Tlim relationship remains consistent across sexes and force vs. position tasks.

Background This study investigated athlete knowledge of the World Anti-doping Agency (WADA) Prohibited Substances List and the effects of four well-known performance enhancing substances (PES). Methods A sample of 1925 elite and sub-elite athletes (mean age 20.6 years) completed a questionnaire about the banned status of 30 substances/methods and their knowledge of the effects of amphetamines, anabolic steroids, growth hormone and erythropoietin. Results Athletes showed limited understanding of the WADA Prohibited Substances List, scoring 32.2% correct, 36.3% incorrect, and 31.4% indicated they did not know the status of 30 substances. Responses of >50% correct were given for only eight substances/method: anabolic steroids, amphetamines, blood doping, erythropoietin, caffeine, vitamins/minerals, protein powders and iron. Athletes demonstrated moderate knowledge of the desired effects of the four PES (49% correct), but poor knowledge of their adverse effects (29% correct). Age, sex, ethnicity, professional/amateur status, and current competition level were significant predictors of the number of correct responses (r2 = 0.16, p

Few studies have investigated the effect of maternal factors on child eating practices. Our study aimed to explore mother–child dietary behaviours and their associations with socio-demographic factors. A cross-sectional analysis was conducted using data from control participants (n 243) in the Healthy Beginnings Trial, which involved first-time mothers and their 2-year-old children. Mother–child dietary behaviours were assessed using short dietary questions (short FFQ) and their associations with socio-demographic factors were examined using binary logistic regression. The dietary intake of 2-year-old children was characterised by low vegetable consumption and high discretionary food intake. In multivariate analysis, lower-income mothers (0·5 cups/d) AOR 2·93 (95 % CI 1·03, 8·35), compared with older mothers (≥25 years). Non-Australian-born mothers reported their child consumed more fruit juice (>0·5 cups/d) AOR 2·04 (95 % CI 1·02, 4·05), sweet snacks AOR 1·96 (95 % CI 1·02, 3·76) and fast food (≥2 times/week) AOR 3·67 (95 % CI 1·29, 10·43) compared with Australian-born mothers. Significant positive correlations between maternal and child dietary intake were observed for all dietary variables except milk, with the largest association for fast foods (Pearson’s r 0·52, P

Currently, it is unclear whether manipulation of movement velocity during resistance exercise has an effect on hypertrophy of specific muscles. The purpose of this systematic review of literature was to investigate the effect of movement velocity during resistance training on muscle hypertrophy. Five electronic databases were searched using terms related to movement velocity and resistance training. Inclusion criteria were randomised and non-randomised comparative studies; published in English; included healthy adults; used dynamic resistance exercise interventions directly comparing fast training to slower movement velocity training; matched in prescribed intensity and volume; duration ≥4 weeks; and measured muscle hypertrophy. A total of six studies were included involving 119 untrained participants. Hypertrophy of the quadriceps was examined in five studies and of the biceps brachii in two studies. Three studies found significantly greater increases in hypertrophy of the quadriceps for moderate-slow compared to fast training. For the remaining studies examining the quadriceps, significant within-group increase in hypertrophy was found for only moderate-slow training in one study and for only fast training in the other study. The two studies that examined hypertrophy of the biceps brachii found greater increases for fast compared to moderate-slow training. Caution is required when interpreting the findings from this review due to the low number of studies, hence insufficient data. Future longitudinal randomised controlled studies in cohorts of healthy adults are required to confirm and extend our findings.

This study sought to achieve radiation dose reductions for patients receiving uterine artery embolisation (UAE) by evaluating radiation dose measurements for the preceding generation (Allura) and upgraded (Azurion) angiography system. Previous UAE regression models in the literature could not be applied to this centre’s practice due to being based on different angiography systems and radiation dose predictor variables. The aims of this study were to establish whether radiation dose is reduced with the upgraded angiography system and to develop a regression model to determine predictors of radiation dose specific to the upgraded angiography system. A comparison between Group I (Allura, n = 95) and Group II (Azurion, n = 95) demonstrated a significant reduction in kerma-area product (KAP) and Ka, r (reference air kerma) by 63% (143.2 Gy cm2 vs 52.9 Gy cm2; P < 0.001, d = 0.8) and 67% (0.6 Gy vs 0.2 Gy; P < 0.001, d = 0.8), respectively. The multivariable linear regression (MLR) model identified the UAE radiation dose predictors for KAP on the upgraded angiography system as total fluoroscopy dose, Ka, r, and total uterus volume. The predictive accuracy of the MLR model was assessed using a Bland-Altman plot. The mean difference was 0.39 Gy cm2 and the limits of agreement were +28.49 and −27.71 Gy cm2, and thus illustrated no proportional bias. The resultant MLR model was considered system-dependent and validated the upgraded angiography system and its advance capabilities to significantly reduce radiation dose. Interventional radiologist and interventional radiographer familiarisation of the system’s features and the implementation of the newly established MLR model would further facilitate dose optimisation for all centres performing UAE procedures using the upgraded angiography system.

Calibration of neuromusculoskeletal models using functional tasks is performed to calculate subject-specific musculotendon parameters, as well as coefficients describing the shape of muscle excitation and activation functions. The objective of the present study was to employ a neuromusculoskeletal model of the shoulder driven entirely from muscle electromyography (EMG) to quantify the influence of different model calibration strategies on muscle and joint force predictions. Three healthy adults performed dynamic shoulder abduction and flexion, followed by calibration tasks that included reaching, head touching as well as active and passive abduction, flexion and axial rotation, and submaximal isometric abduction, flexion and axial rotation contractions. EMG data were simultaneously measured from 16 shoulder muscles using surface and intramuscular electrodes, and joint motion evaluated using video motion analysis. Muscle and joint forces were calculated using subject-specific EMG-driven neuromusculoskeletal models that were uncalibrated and calibrated using (i) all calibration tasks (ii) sagittal plane calibration tasks, and (iii) scapular plane calibration tasks. Joint forces were compared to published instrumented implant data. Calibrating models across all tasks resulted in glenohumeral joint force magnitudes that were more similar to instrumented implant data than those derived from any other model calibration strategy. Muscles that generated greater torque were more sensitive to calibration than those that contributed less. This study demonstrates that extensive model calibration over a broad range of contrasting tasks produces the most accurate and physiologically relevant musculotendon and EMG-to-activation parameters. This study will assist in development and deployment of subject-specific neuromusculoskeletal models.

The availability of keyboards with reduced key width has been recently promoted as an ergonomic aid for small-handed pianists to overcome any potential physical disadvantages that may restrict their piano repertoire. However, a lack of biomechanical data exists to support whether reduced piano key size is effective in achieving this outcome. This research investigates the effect of playing on three different key width size pianos (5.5-inch octave, 6.0-inch octave and conventional size with 6.5-inch octave) on hand, arm and shoulder muscle activity levels according to the hand size of the pianists. Results indicate that piano key size affects the muscle activity levels of selected muscles. Furthermore, this effect of different key sizes changed according to the players’ hand spans. Small-handed pianists may benefit from using smaller-sized keyboards to reduce muscular exertion during performance. This investigation provides preliminary EMG data supporting the use of different size keyboards to improve the ergonomic fit according to the dimensions of individual pianists.

Context: Rugby union is a physically demanding collision sport with high injury rates. There is a common perception that higher training loads result in greater injury risk in field-based sports. Objectives: To determine injury, anthropometric, and physical-performance characteristics in junior rugby union players and investigate the interaction between training load and injury across a competitive season. Design: Prospective cohort study. Methods: Fifty-one players (age 19.2 ± 0.7 y) from an under-20 university rugby union team (forwards, n = 27; backs, n = 24) participated in a study conducted over a competition season. Training load, injury characteristics, anthropometry, physiological performance, and match time-loss injury incidence were observed. Results: Backs had significantly lower body mass (ES [95% CI] = 1.6 [0.9, 2.2]), skinfold thickness (ES = 1.1 [0.5, 1.7]), strength (squat ES = 0.6 [0.0, 1.2], deadlift ES = 0.6 [0.0, 1.1], bench press ES = 0.9 [0.4, 1.5]), lower-body power (ES = 0.4 [−0.2, 1.0]), and higher maximal aerobic capacity (ES = −0.3 [−0.8, 0.3]) than forwards. Match injury incidence was 107.3 injuries/1000 player hours (forwards 91.4/1000, backs 125.5/1000) during preseason and 110.7 injuries/1000 player hours (forwards 124.1/1000, backs 95.2/1000) during in-season. Forwards showed higher incidence of joint and ligament (P = .049) and upper-limb (P = .011) injuries than backs. No significant relationship between overall training load and match injury incidence was found. However, lower match injury incidence was associated with higher weekly training volume in backs (P = .007). Conclusions: Positional differences in body composition, performance, injury characteristics, and match injury patterns were identified in junior university rugby union players, indicating the need for position-specific training programs to reduce risk of injury.

To report on the reliability and validity of a Diet Quality Index (DQI) to assess preschoolers dietary patterns using a short food frequency questionnaire (sFFQ) and 3-day food records (3d-FR). Seventy-seven preschool carers/parents completed a telephone interview on preschoolers (2–5-year olds) dietary habits in metropolitan Sydney. Agreement in scores was assessed using intraclass correlation (ICC) and paired t-tests for repeated sFFQ–DQI scores and Bland–Altman methods and paired t-tests for sFFQ–DQI and 3d-FR–DQI scores. Mean-total sFFQ–DQI ICC scores was high = 0.89, 95% CI (0.81, 0.93). There was weak agreement between sFFQ–DQI and 3d-FR–DQI scores (r = 0.36, p

Commercially available exergames that are for wheelchair-bound individuals with spinal cord injury (SCI) are scarce. This study sought to identify exergames for individuals with SCI that are "dose-potent" for health benefits.Six participants with SCI were recruited for a pilot study to investigate the exercise intensity of selected exergames (Move Tennis, Move Boxing, and Move Gladiator Duel) for the potential to improve health. Issues relating to exergaming for individuals with SCI were identified, and a Move Kayaking exergame was conceived using relevant design processes in an iterative manner. These processes included the following: participant needs and requirements, system requirements (hardware), system architecture (physical and operational views), and integration and verification of the finished system. Emphasis was given to operational and physical designs of the Move Kayaking exergame.Move Boxing, Move Gladiator Duel, and Move Kayaking achieved moderate intensity exercise, while Move Tennis only achieved exercise of low intensity based on participants' metabolic equivalent. However, all four exergames achieved at least moderate intensity based on individuals' ratings of perceived exertion (RPE).The intensity classification while playing Move Boxing, Move Tennis, Move Gladiator Duel, and Move Kayaking, using RPE, reported adequate exercise intensities prescribed by exercise guidelines.

Hackett, DA, Cobley, SP, Davies, TB, Michael, SW, and Halaki, M. Accuracy in estimating repetitions to failure during resistance exercise. J Strength Cond Res 31(8): 2162-2168, 2017-The primary aim of this study was to assess the accuracy in estimation of repetitions to failure (ERF) during resistance exercise. Furthermore, this investigation examined whether the accuracy in ERF was affected by training status, sex, or exercise type. Eighty-one adults (men, n = 53 and women, n = 28) with broad range of resistance training experience participated in this study. Subjects performed up to 10 sets of 10 repetitions at 70% 1 repetition maximum (1RM) and 80% 1RM for the chest press and leg press, respectively. At the completion of each set, subjects reported their ERF and then continued repetitions to failure to determine actual repetitions to failure (ARF). The accuracy (amount of error) of ERF was determined over an ARF 0-10. Significant differences were found for error of ERF among ARF (p0.001), with the error of ERF ∼1 repetition at ARF 0-5 compared with2 repetitions at ARF 7-10. Greater accuracy was found for the chest press compared with leg press, with the error of ERF ≤1 repetition for ARF 0-5 and ARF 0-3, respectively (p = 0.012). Men were found to be more accurate than women at specific ARFs for the leg press (p = 0.008), whereas no interaction was found for the chest press. Resistance training experience did not affect the accuracy in ERF. These results suggest that resistance trainers can accurately estimate repetitions to failure when close to failure and that ERF could importantly be practically used for prescription and monitoring of resistance exercise.

Objectives Optimal shoulder rotation range of motion (ROM) for swimming is unknown. The primary aim of this study was to examine shoulder rotation ROM in elite swimmers, including the influence of humeral torsion on rotation ROM, in order to establish optimal shoulder rotation parameters for swimming. In addition, we examined the relationship between rotation ROM and shoulder pain. Design Descriptive cohort study. Methods Seventy elite Australian swimmers provided shoulder pain history data prior to measurement of humeral torsion and passive and active shoulder rotation ROM. Repeated measure analyses of variance were used to investigate within and between participant differences for all variables. Associations between humeral torsion and rotation ROM were investigated using Pearson's correlation coefficient. Multiple regression analysis was utilised to examine the associations between rotation ROM and shoulder pain. Results Average humeral torsion angles of 27±10° (dominant side) and 31±10° (non-dominant side) were demonstrated in this elite swimming cohort. In general, increased humeral torsion was positively associated with increased internal rotation (IR) and decreased external rotation (ER) ROM. There were significant differences in both IR and ER ROM measured passively and actively (F 2,136 ≥93.1, p 2 =0.058; p=0.46). Conclusions Humeral torsion angle and passive shoulder IR ROM were similar while passive ER ROM was greater in elite swimmers compared to reported normal population values.

Ball, S, Halaki, M, and Orr, R. Movement demands of rugby sevens in men and women: A systematic review and meta-analysis. J Strength Cond Res 33(12): 3475-3490, 2019-Global positioning systems (GPS) provide comprehensive information of player movement demands in rugby 7's. Although studies have investigated the use of GPS within many field-based team sports, the application of GPS within rugby 7's remains unclear. The aim of this review was to evaluate the movement demands and conduct a meta-analysis on comparable GPS measures to assess player movement in rugby 7's. A systematic search of electronic databases Medline, SPORTDiscus, Cinahl, Web of Science, Scopus, and Embase was performed. The search strategy combined terms covering: global positioning systems AND rugby union. Studies were included if they contained rugby sevens' players monitored by GPS. Meta-analyses were conducted to provide a pooled mean and confidence intervals (CIs) on outcomes for data extracted from at least 3 studies. A total of 24 publications were eligible for review and included 661 (447 male and 214 female) rugby 7's players. Meta-analysis indicated that male players cover greater relative distance (male: 108.5 m·min, 95% CI [104.9-112.1] m·min, female: 100.3 m·min, 95% CI [96.0-104.7] m·min), distance at >12.6 km·h (male: 449.3 m, 95% CI [427.0-471.5] m, female: 339.5 m, 95% CI [291.1-387.9] m) and >18.0 km·h (male: 190.3 m, 95% CI [180.7-199.9] m, female: 129.9 m, 95% CI [99.9-159.8] m), and have a greater maximum velocity compared with female players (male: 29.8 km·h, 95% CI [29.2-30.4] km·h, female: 24.6 km·h, 95% CI [23.3-25.9] km·h), whereas relative distance is higher for the first half (109.5 m·min, 95% CI [99.1-120.0] m·min) compared with the second half (93.8 m·min, 95% CI [87.4-100.1] m·min) of match play across sexes and playing levels. Independent velocity zone classifications should apply for male and female players, whereas velocity thresholds should remain consistent across studies. Rugby 7's training intensity should vary between male and female players.

This systematic review aimed to evaluate whether muscle activity and playing-related musculoskeletal disorders are associated with musicians' anthropometrics and their instrument size or set-up during violin and piano performance. Studies were retrieved systematically from six databases on 1 April 2019 combined with hand searching results. The Appraisal tool for Cross-Sectional Studies (AXIS tool) was used to evaluate the methodological quality of the included papers. A total of twenty articles were identified. Most included studies focussed on either the adjustment of the shoulder rest in violinists, or the hand size in pianists. However, methodological quality was inconsistent. The electromyography data reported by the included studies were not appropriately processed and interpreted. Studies generally reported the use of a shoulder rest changes muscle activity and smaller hand size is correlated to increased playing-related musculoskeletal disorders incidence. However, no conclusions can be drawn due to heterogeneity and low quality of methodology in the available literature.

Davies, TB, Halaki, M, Orr, R, Helms, ER, and Hackett, DA. Changes in bench press velocity and power after 8 weeks of high-load cluster- or traditional-set structures. J Strength Cond Res 34(10): 2734-2742, 2020-This study investigated the effects of high-load cluster- vs. traditional-set structures using the bench press on velocity and power. Twenty-one resistance-trained individuals (male = 12, female = 9) performed a 3-week familiarization block followed by randomization into 1 of 2 upper- and lower-body split training routines performed for 8 weeks. The bench press was the only exercise manipulated with subjects using either cluster-set (CLUS, n = 11) or traditional-set (TRAD, n = 10) structures during training sessions. Subjects performed 4 sets of 5 repetitions at 85% 1 repetition maximum (1RM) with CLUS having a 30-second inter-repetition, and 3-minute interset rest while TRAD had a 5-minute interset rest. A load-velocity profile of relative loads derived from a 1RM test was used to assess velocity and power (absolute and relative to body mass) on the bench press. Significant improvements over time were found across various loads ranging from 45 to 75% 1RM for absolute and relative peak power (p = 0.006-0.041), and mean power (p = 0.001-0.032). Significant decreases over time were found at 55% 1RM and 65% 1RM for peak velocity (p = 0.027 and p = 0.012, respectively) and mean velocity (p = 0.047 and p = 0.022, respectively). There were no significant group or group by time interactions found for all outcomes. Within the context of high-load resistance training, set structure seems to be of less importance for changes in bench press velocity and power provided there is an intention to lift with maximal concentric velocity.

The growing interest in preserving cognition through video games in the ageing population is evidenced by its wealth of literature. However, there has been a lack of consensus on video games efficacy and even limited understanding on the factors moderating its effectiveness. The present review sought to evaluate video game effects, relative to no-game control condition, on cognitive functions in older adults. The functions included processing speed, attention, delayed memory, reasoning, and executive functions (inhibition, shifting and updating memory). Personal and methodological moderators were explored to explain the variability in cognitive effects using meta-regression. Through a systematic literature search of online databases, 27 intervention studies were eligible, with a total of 1126 participants, for analysis. Using random-effect models, small but significant training effects were found on updating memory but none were detected in other cognitive functions. The heterogeneity across studies was in general high for all cognitive functions and was partially accounted for, in all cognitive functions except for inhibition and updating, by different moderators such as the proportion of females, outcome measure parameters, training intensity, and game type. The findings highlight limited effects of video games on cognitive functions that were largely influenced by factors related to study design.

Movement velocity is an acute resistance-training variable that can be manipulated to potentially optimize dynamic muscular strength development. However, it is unclear whether performing faster or slower repetitions actually influences dynamic muscular strength gains. We conducted a systematic review and meta-analysis to examine the effect of movement velocity during resistance training on dynamic muscular strength. Five electronic databases were searched using terms related to movement velocity and resistance training. Studies were deemed eligible for inclusion if they met the following criteria: randomized and non-randomized comparative studies; published in English; included healthy adults; used isotonic resistance-exercise interventions directly comparing fast or explosive training to slower movement velocity training; matched in prescribed intensity and volume; duration ≥4 weeks; and measured dynamic muscular strength changes. A total of 15 studies were identified that investigated movement velocity in accordance with the criteria outlined. Fast and moderate-slow resistance training were found to produce similar increases in dynamic muscular strength when all studies were included. However, when intensity was accounted for, there was a trend for a small effect favoring fast compared with moderate-slow training when moderate intensities, defined as 60–79% one repetition maximum, were used (effect size 0.31; p = 0.06). Strength gains between conditions were not influenced by training status and age. Overall, the results suggest that fast and moderate-slow resistance training improve dynamic muscular strength similarly in individuals within a wide range of training statuses and ages. Resistance training performed at fast movement velocities using moderate intensities showed a trend for superior muscular strength gains as compared to moderate-slow resistance training. Both training practices should be considered for novice to advanced, young and older resistance trainers targeting dynamic muscular strength.

Aim To investigate the relationship between training volume and soft tissue injury incidence, and characterise soft tissue injury in rugby union players. Design A systematic search of electronic databases was performed. The search strategy combined terms covering: training volume and injury, and rugby union, and players of all levels. Data sources Medline, SPORTDiscus, Web of Science, Embase, PubMed. Eligibility criteria for selecting studies Studies were included if they reported: male rugby union players, a clear definition of a rugby union injury, the amount of training volume undertaken by participants, and epidemiological data for soft-tissue injuries including the number or incidence. Results 15 studies were eligible for inclusion. Overall match and training injury incidence ranged from 3.3 to 218.0 injuries/1000 player match hours and 0.1–6.1 injuries/1000 player training hours, respectively. Muscle and tendon as well as joint (non-bone) and ligament injuries were the most frequently occurring injuries. The lower limb was the most prevalent injury location. Injury incidence was higher in professional rugby union players than non-professional players. Contact events were responsible for the greatest injury incidence. For non-contact mechanisms, running was responsible for the highest injury incidence. Inconsistent injury definitions hindered reliable comparison of injury data. The lack of reporting training volumes in hours per player per week limited the ability to investigate associations between training volume and injury incidence. Conclusions A higher level of play may result in higher match injury incidence. Muscle and tendon injuries were the most common type of soft tissue injury, while the lower limb was the most common location of injury in rugby union players, and running was responsible for the highest injury incidence during non-contact events.

In dance, the goals of actions are not always clearly defined. Investigations into the perceived quality of dance actions and their relation to biomechanical motion should give insight into the performance of dance actions and their goals. The purpose of this review was to explore and document current literature concerning dance perception and its relation to the biomechanics of motion. Seven studies were included in the review. The study results showed systematic differences between expert, non-expert, and novice dancers in biomechanical and perceptual measures, both of which also varied according to the actions expressed in dance. Biomechanical and perceptual variables were found to be correlated in all the studies in the review. Significant relations were observed between kinematic variables such as amplitude, speed, and variability of movement, and perceptual measures of beauty and performance quality. However, in general, there were no clear trends in these relations. Instead, the evidence suggests that perceptual ratings of dance may be specific to both the task (the skill of the particular action) and the context (the music and staging). The results also suggest that the human perceptual system is sensitive to skillful movements and neuromuscular coordination. Since the value perceived by audiences appears to be related to dance action goals and the coordination of dance elements, practitioners could place a priority on development and execution of those factors.

Objectives Load is used to increasingly challenge muscle function and has been shown to increase muscle activity levels with no change in activation patterns during shoulder flexion, extension, adduction and rotation. However, the effect of load during shoulder abduction, a movement commonly used in assessment of shoulder dysfunction and to improve shoulder function, has not been comprehensively examined. Therefore, the purpose of this study was to determine if load influences shoulder muscle activation patterns and levels during scapular plane abduction in normal subjects. Design Experimental study. Methods Fourteen volunteers performed shoulder abduction in the scapular plane at 25%, 50% and 75% of maximum load. Eight shoulder muscles were investigated using a combination of indwelling and surface electromyographic recordings: middle deltoid, infraspinatus, subscapularis, supraspinatus, serratus anterior, upper and lower trapezius and rhomboid major. Results All muscles tested showed increasing average muscle activation levels with increasing load and strong correlations in the activation patterns between loads. Conclusions Increasing shoulder abduction load not only increases activity in middle deltoid but also in the rotator cuff (infraspinatus, subscapularis, supraspinatus) and axioscapular (serratus anterior, upper and lower trapezius, rhomboid major) muscles. The functional stabilising role of both the rotator cuff and axioscapular muscles is considered an important contribution to the increased activation levels in these muscle groups as they function to counterbalance potential translation forces produced by other muscles during shoulder abduction. The activation patterns of all shoulder muscle groups during abduction can be trained at low load and progressively challenged with increasing load.

usc Refereed/Peer-reviewed The purpose of this study was to apply a time-motion model to estimate and describe the energy expenditure and metabolic power demands of playing positions in elite rugby league match-play, utilizing Global Positioning System (GPS) devices. 18 elite rugby league players participated in this study. Players' positional groups included: outside backs (n=59 files, n=4 players), adjustables (n=74 files, n=4 players), wide-running (n=104 files, n=7 players) and hit-up forwards (n=36 files, n=3 players). Outside backs expended the greatest total energy (40.1±5.0 kJ·kg-1) per match, equivalent to 8.1%, 26.6% and 61.9% greater energy than adjustables, wide-running and hit-up forwards, respectively. Adjustables attained an anaerobic index 7.3% higher than wide-running forwards, 19.7% higher than hit-up forwards (p=0.001) and 43.2% higher than outside backs (p

Warm-up is commonly recommended for injury prevention and performance enhancement across all activities, yet this recommendation is not supported by evidence for repetitive submaximal activities such as instrumental music performance.The objective of this study is to quantify the effects of cardiovascular, core muscle, and musical warm-ups on muscle activity levels, musical performance, and subjective experience in skilled violinists.Fifty-five undergraduate, postgraduate, or professional violinists performed five randomly ordered 45-s musical excerpts of varying physical demands both before and after a randomly assigned 15-min, moderate-intensity cardiovascular, core muscle, musical (technical violin exercises), or inactive control warm-up protocol. Surface EMG data were obtained for 16 muscles of the trunk, shoulders, and right arm during each musical performance. Sound recording and perceived exertion (RPE) data were also obtained. Sound recordings were randomly ordered and rated for performance quality by blinded adjudicators. Questionnaire data regarding participant pain sites and fitness levels were used to stratify participants according to pain and fitness levels. Data were analyzed using two- and three-factor ANCOVA (surface EMG and sound recording) and Wilcoxon matched pairs tests (RPE).None of the three warm-up protocols had significant effects on muscle activity levels (P ≥ 0.10). Performance quality did not significantly increase (P ≥ 0.21). RPE significantly decreased (P0.05) after warm-up for each of the three experimental warm-ups; control condition RPE did not significantly decrease (P0.23).Acute physiological and musical benefits from cardiovascular, core muscle, and musical warm-ups in skilled violinists are limited to decreases in RPE. This investigation provides data from the performing arts in support of sports medical evidence suggesting that warm-up only effectively enhances maximal strength and power performance.

Because of its superficial location, surface electrodes are commonly used to record lower trapezius activity. Recent evidence, however, would suggest that surface electromyography is not a valid to record activity from other superficially placed shoulder muscles. Therefore, the aim of this study was to determine the validity of using surface electrodes to record lower trapezius activity. Ten asymptomatic subjects performed ramped isometric (0–100% maximum load) and dynamic (70% maximum load) shoulder tasks. Intramuscular electrodes were inserted into lower trapezius and rhomboid major. Surface electrodes were placed over lower trapezius around the intramuscular electrodes. Differences in the recorded activity of lower trapezius between surface and intramuscular electrodes were tested using a 2 factor repeated measures analysis of variance with factors: test and electrode type. Similarity in the recorded activity patterns between the two electrodes was tested using Pearson’s correlation coefficient (r). Results indicated that there was no difference in lower trapezius activity levels (p = 0.98) or activation patterns (r ≥ 0.74) recorded by the intramuscular and surface electrodes. The results of this study indicate that any potential crosstalk contamination in the surface electrode signal is having little influence on the recorded activity from lower trapezius and therefore, support the common practice of surface electromyography to investigate lower trapezius function.

Purpose The Physical Activity Scale for Individuals with Physical Disabilities questionnaire provides an assessment of physical activity after spinal cord injury. This study sought to adapt, with cultural competence, the English questionnaire and translate it into Bahasa Malaysia, including evaluation of content and face validity, internal consistency and test-retest reliability, and completion of a factor analysis in order to validate the Malaysian version. Materials and methods A total of 250 participants completed the questionnaire that was distributed via email, postal mail, the internet, physically and by word of mouth. Sixty-eight respondents were re-contacted to complete the questionnaire again. Results The adapted PASIPD demonstrated adequate internal consistency Cronbach's α = 0.68 and acceptable test-retest reliability, intraclass correlation = 0.87. Factor analysis extracted four main dimensions for physical activity; factor 1 (heavy housework, home repair, lawn work and gardening), factor 2 (sports and recreation), factor 3 (light housework and caring for another person) and factor 4 (leisure and occupational activities) that accounted for 64% of the physical activities' total variance. Conclusion The Malaysian-adapted English and translated Bahasa Malaysia versions of the questionnaires intended to measure physical activity levels in individuals with spinal cord injury, demonstrated good to acceptable validity and reliability. However, some individual items revealed weak reliability measures. Further work is needed to validate the questionnaire's criterion validity against other physical activity measures. Implications for rehabilitation The Malaysian adaptation of the Physical Activity Scale for Individuals with Physical Disabilities questionnaire provided preliminary support for its use since it has demonstrated adequate construct validity and reliability. The Malaysian adaptation of the Physical Activity Scale for Individuals with Physical Disabilities questionnaire can quantify the physical activity level of community-dwelling individuals with spinal cord injury, whilst deriving descriptive information on their physical activities. Deploying the Physical Activity Scale for Individuals with Physical Disabilities questionnaire to a spinal cord injury population in Malaysia may provide the first data on activities of daily living in an Asian developing country.

This study examined differences across skill levels in the kinematics of a complex, whole-body, asymmetrical, cyclical dance sequence, the ‘Alternate Basic’ in Cha-Cha-Cha, to determine whether observed differences were consistent with Bernstein's (1967) model of development of coordination. Bernstein proposed that with novel motor skills, beginners move their bodies rigidly and spastically, freezing kinematic degrees of freedom (DOF) to constrain the motor system. As the skill becomes practised, the DOF unfreeze and movements become more dynamic, allowing the integration of reactional elements (passive forces, moments, etc.) and organisation of more complex coordinative structures. Twenty-nine dancers - beginners (n = 10), intermediates (n = 10), experts (n = 9) - performed 12 cycles of the dance sequence (total duration ~60 s). Three-dimensional kinematic data from 36 joint angles were collected using a 14-camera infrared motion capture system. Most joints displayed increased amplitude and speed of movement, especially early in skill progression (beginner-intermediate stage), with no evidence of any decreases, showing that unfreezing occurred around the general movement pattern early. Speed of movement continued to increase later (intermediate-expert stage), as well as further unfreezing of the upper limbs. Changes to intra-limb couplings were limited, comprising some early reductions in coupling strength. Principal component analyses (PCA) showed that the structure of movement became more organised with increased skill. There was an early reduction in the number of coordinative structures, while later, movement was integrated more into the first coordinative structure. As predicted by Bernstein's coordination development model, therefore, the kinematic DOF unfroze as skill level progressed, leading to increased organisation of coordinative structures. The results of this study support the importance of a whole-body perspective in studies of coordination, with incorporation of kinetic variables in future research in order to examine the role that reactional elements play in motor skill development.

INTRODUCTION Balance impairment contributes to gait dysfunction, falls, and reduced quality of life in adults with Charcot-Marie-Tooth disease (CMT) but has been minimally examined in pediatric CMT. METHODS The CMT Pediatric Scale (CMTPedS) was administered to 520 children with CMT. Associations between balance function (Bruininks-Oseretsky Test of Motor Proficiency [BOT-2]) and sensorimotor and gait impairments were investigated. RESULTS Daily trips/falls were reported by 42.3% of participants. Balance (BOT-2) varied by CMT subtype, was impaired in 42% of 4-year-olds, and declined with age (P < 0.001). Vibration (P < 0.001), pinprick (P < 0.004), ankle dorsiflexion strength (P < 0.001), and foot alignment (P < 0.004) were associated with BOT-2 balance (adjusted R2 = 0.28). The visual dependence of balance increased with age. DISCUSSION Balance impairment occurs from a young age in children with CMT. Balance intervention studies are required in pediatric CMT and should consider the degree of sensorimotor impairment, foot malalignment, and visual dependence. Muscle Nerve, 2019.

This study analysed nutritional parameters (baseline body mass index (BMI), weight changes and enteral nutrition (EN) use, and their association with hospital admissions during radiotherapy in patients with head and neck cancer (HNC)).A retrospective review of patients diagnosed with HNC and treated with radiotherapy between October 2012 and April 2014 was conducted. Data on each subject's diagnosis, age, sex, chemotherapy, previous surgery, EN use, weight changes, and BMI were examined for their association with hospital admissions during treatment.Eighty-three patients were included, mean age (±standard deviation) = 61 (± 11 years). Thirty-four percent had self-reported weight loss at diagnosis, and mean BMI was 26.2 ± 5.3 kg/mCritical weight loss during radiotherapy was associated with unplanned nutrition-related hospital admissions. Higher BMI was associated with greater weight loss during radiotherapy, whilst EN use assisted in weight preservation. Further research around patient selection for nutritional interventions aimed at preventing critical weight loss and unplanned hospital admissions is needed.

The purpose of this systematic review and meta-analysis is to assess the effect of concurrent high intensity interval training (HIIT) and resistance training (RT) on strength and hypertrophy. Five electronic databases were searched using terms related to HIIT, RT, and concurrent training. Effect size (ES), calculated as standardised differences in the means, were used to examine the effect of concurrent HIIT and RT compared to RT alone on muscle strength and hypertrophy. Sub-analyses were performed to assess region-specific strength and hypertrophy, HIIT modality (cycling versus running), and inter-modal rest responses. Compared to RT alone, concurrent HIIT and RT led to similar changes in muscle hypertrophy and upper body strength. Concurrent HIIT and RT resulted in a lower increase in lower body strength compared to RT alone (ES = -0.248, p = 0.049). Sub analyses showed a trend for lower body strength to be negatively affected by cycling HIIT (ES = -0.377, p = 0.074) and not running (ES = -0.176, p = 0.261). Data suggests concurrent HIIT and RT does not negatively impact hypertrophy or upper body strength, and that any possible negative effect on lower body strength may be ameliorated by incorporating running based HIIT and longer inter-modal rest periods.

Study Design Observational: cross-sectional study. Background Idiopathic frozen shoulder is a common cause of severe and prolonged disability characterised by spontaneous onset of pain with progressive shoulder movement restriction. Although spontaneous recovery can be expected the average length of symptoms is 30 months. Chronic inflammation and various patterns of fibrosis and contracture of capsuloligamentous structures around the glenohumeral joint are considered to be responsible for the signs and symptoms associated with frozen shoulder, however, the pathoanatomy of this debilitating condition is not fully understood. Objectives To investigate the feasibility of a muscle guarding component to movement restriction in patients with idiopathic frozen shoulder. Methods Passive shoulder abduction and external rotation range of motion (ROM) were measured in patients scheduled for capsular release surgery for frozen shoulder before and after the administration of general anaesthesia. Results Five patients with painful, global restriction of passive shoulder movement volunteered for this study. Passive abduction ROM increased following anaesthesia in all participants, with increases ranging from approximately 55°–110° of pre-anaesthetic ROM. Three of these participants also demonstrated substantial increases in passive external rotation ROM following anaesthesia ranging from approximately 15°–40° of pre-anaesthetic ROM. Conclusion This case series of five patients with frozen shoulder demonstrates that active muscle guarding, and not capsular contracture, may be a major contributing factor to movement restriction in some patients who exhibit the classical clinical features of idiopathic frozen shoulder. These findings highlight the need to reconsider our understanding of the pathoanatomy of frozen shoulder. Level of evidence Level 4.

This study investigated whether short-term heart rate variability (HRV) can be used to differentiate between the immediate recovery periods following three different intensities of preceding exercise. 12 males cycled for 8 min at three intensities: LOW (40–45 %), MOD (75–80 %) and HIGH (90–95 %) of heart rate (HR) reserve. HRV was assessed during exercise and throughout 10-min seated recovery. 1-min HR recovery was reduced following greater exercise intensities when expressed as R–R interval (RRI, ms) (p