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Purpose: This study examined the relationships between training workloads, game workloads, and match performance in an elite netball team. Methods: Ten elite female netball athletes were monitored over a complete season. Training and game external workloads were determined through inertial movement units and expressed as absolute PlayerLoad (PL) and change of direction (COD). Monthly workload and training efficiency index were also calculated, which used internal workloads (session rating of perceived exertion and summated heart-rate zones). Game performance was assessed through a performance analysis statistic algorithm called NetPoints. To account for the influence of team game workloads on each other, the average workload for midcourt positions (avgMC) was calculated for each game. Data for each athlete were transformed into z scores, and linear mixed modeling was used to build models to examine the relationships between workloads and game performance. Results: Monthly PL, training efficiency index PL, and avgMC PL were statistically significant (P <.05) and positively related to game PL (z = 0.20–0.35, P <.001–.02). For game COD, statistically significant positive relationships were found between monthly COD (z = 0.29 [0.11], P =.01) and avgMC COD (z = 0.21 [0.09], P =.03). The models for NetPoints found significant negative relationships with monthly PL (z = 0.46 [0.12], P <.001) and COD (z = −0.36 [0.11], P =.01). Conclusions: Higher monthly workloads are related to higher game workload; however, they are also related to decreases in match performance. Therefore, netball practitioners should consider that increases to training workload in a 4-week period prior to a game can influence game workloads and performance. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine responses at 3 and 27 hours after low-load jump squat (LL) and maximal isometric half-squat (ISO) priming stimuli. Fifteen resistance-trained males performed LL (4 3 3 at 20% 1 repetition maximum [1RM]), ISO (4 3 3 seconds), and control (CON) activities (standardized warm-up) in a randomized and counterbalanced order. Countermovement jump (CMJ) and isometric midthigh pull tests were conducted to assess performance changes after priming and CON activities. No clear changes in CMJ measures were found after priming activities compared with CON. However, small effect size improvements were found after priming stimuli completed on the same day. A 2.9% decrease in concentric phase duration (CI 5 0.3-5.9, p 5 0.333, Cliff's delta520.156) and a 9.1% increase in RSImod (CI 50.2-12.3, p50.151, Cliff's delta520.218) occurred at 3 hours after LL compared with CON. Braking phase duration (CI 5 0.8-10.6, p 5 0.333, Cliff's delta520.213) was 2.9% shorter at 3 hours after ISO compared with CON. No clear changes in isometric peak force occurred after priming activities compared with CON. Additionally, questionnaires were completed to assess perceptual state and perceived effectiveness of the priming stimulus to influence performance. An increase in the "effect of activity" was perceived at 3 hours after LL and ISO (p 5 0.013-0.044, Cliff's delta 5 0.578-0.6) and at 27 hours after ISO (p 5 0.99, Cliff's delta 5 0.173) compared with CON. An increase in "muscular heaviness" was also reported at 3 hours after ISO compared with CON (p 5 0.199, Cliff's delta 5 0.320). The collective findings suggest limited benefits over the day after LL and ISO priming stimuli. However, as there was substantial variation in individual responses, the relative nature of priming responses should be considered when prescribing similar strategies in practical environments. [ABSTRACT FROM AUTHOR]

High intensity interval training (HIIT) has been shown to consistently elicit rapid and significant adaptations in a number of physiological systems, across many different healthy and clinical populations. In addition, there is increasing interest in how some acute, yet transient responses to high intensity exercise potentially reduce the risks of particular diseases. Recent work has shown that discrete, brief bouts of high intensity exercise (termed 'exercise snacks') can improve glucose control and vascular health and thus counter the negative cardiometabolic consequences of prolonged, uninterrupted periods of inactivity. In this brief review, we advance the case, using evidence available from pre‐clinical studies in the exercise oncology literature, that brief, frequently completed bouts of high intensity exercise embedded within an individual's overall daily and weekly physical activity schedule, may transiently impact the tumour microenvironment and improve the health outcomes for those who have been diagnosed and treated for cancer. [ABSTRACT FROM AUTHOR]

Purpose: To examine relationships between external- and internal-workload variables in an elite female netball team, with consideration of positional differences. Methods: Nine elite female netball athletes had their weekly workloads monitored across their preseason and competition phases of a season. Internal workload was determined using summated heart-rate (HR) zones and session ratings of perceived exertion (sRPE), whereas external workload was determined using inertial movement units and included absolute PlayerLoad (PL), relative PL (PL per minute), accelerations (ACCEL), decelerations (DECEL), jumps, changes of direction (COD), high-intensity events, medium-intensity events, low-intensity events, PL in the forward direction, PL in the sideways direction, and PL in the vertical direction. Relationships between external- and internal-workload variables in the team and relative to playing position were examined. Results: Across the team, the strongest external workloads that correlated with summated HR zones were PL ( r= .65), COD ( r= .64), ACCEL (r= .61), and DECEL ir =.61). The strongest external workloads that correlated with sRPE were COD ( r= .79), followed by jumps (r=.76), ACCEL ( r= .75), and DECEL (r=.75). For all positions, except-goal shooter, the strongest con-elation was between PL and sRPE (r = .88-94). In the goal-shooter position, the strongest correlation was between summated HR zones and DECEL (r = .89). Conclusions: The inertial movement unit-derived external-workload variables are strongly related to common internal-workload variables. In particular, COD and sRPE appear to provide a good monitoring combination of external and internal training loads for elite netball players. [ABSTRACT FROM AUTHOR]

This study systematically reviewed all human longitudinal exercise interventions that reported changes in the gut microbiota; frequency, intensity, duration and type of exercise were assessed to determine the influence of these variables on changes to the gut microbiota in both healthy individuals and clinical populations (PROPERO registration: CRD42022309854). Using PRISMA guidelines, trials analysing gut microbiota change with exercise interventions were included independent of trial randomisation, population, trial duration or analysis technique. Studies were excluded when microbiota abundance was not reported or when exercise was combined with other interventions. Twenty-eight trials were included, of which twelve involved healthy populations only and sixteen involved mixed or clinical-only populations. The findings show that participation in exercise of moderate to high-intensity for 30–90 min ≥3 times per week (or between 150–270 min per week) for ≥8 weeks is likely to produce changes in the gut microbiota. Exercise appears to be effective in modifying the gut microbiota in both clinical and healthy populations. A more robust methodology is needed in future studies to improve the certainty of the evidence. [ABSTRACT FROM AUTHOR]

Purpose: To assess the impact of different repeated-high-intensity-effort (RHIE) bouts on player activity profiles, skill involvements, and neuromuscular fatigue during small-sided games, Participants: 22 semiprofessional rugby league players (age 24.0 ± 1.8 y, body mass 95.6 ± 7.4 kg). Methods: During 4 testing sessions, they performed RHIE bouts that each differed in the combination of contact and running efforts, followed by a 5-min off-side small-sided game before performing a second bout of RHIE activity and another 5-min small-sided game. Global positioning system microtechnology and video recordings provided information on activity profiles and skill involvements. A countermovement jump and a plyometric push-up assessed changes in lower- and upper-body neuromuscular function after each session. Results: After running-dominant RHIE bouts, players maintained running intensities during both games. In the contact-dominant RHIE bouts, reductions in moderate-speed activity were observed from game 1 to game 2 (ES = -0.71 to -1.06). There was also moderately lower disposal efficiency across both games after contact-dominant RHIE activity compared with running-dominant activity (ES = 0.62-1.02). Greater reductions in lower-body fatigue occurred as RHIE bouts became more running dominant (ES = -0.01 to-1.36), whereas upper-body fatigue increased as RHIE bouts became more contact dominant (ES - -0.07 to -1.55). Conclusions: Physical contact causes reductions in running intensity and the quality of skill involvements during game-based activities. In addition, the neuromuscular fatigue experienced by players is specific to the activities performed. [ABSTRACT FROM AUTHOR]

Purpose: To determine the influence the number of contact efforts during a single bout has on running intensity during game- based activities and assess relationships between physical qualities and distances covered in each game. Methods: Eighteen semiprofessional rugby league players (age 23.6 ± 2.8 y) competed in 3 off-side small-sided games (2 x 10-min halves) with a contact bout performed every 2 min. The rules of each game were identical except for the number of contact efforts performed in each bout. Players performed 1, 2, or 3 x 5-s wrestles in the single-, double-, and triple-contact game, respectively. The movement demands (including distance covered and intensity of exercise) in each game were monitored using global positioning system units. Bench-press and back-squat 1-repetition maximum and the 30-15 Intermittent Fitness Test (30--15IFT) assessed muscle strength and high-intensity-running ability, respectively. Results: There was little change in distance covered during the single- contact game (ES = -0.16 to -0.61), whereas there were larger reductions in the double- (ES = -0.52 to -0.81) and triple-contact (ES = -0.50 to -1.15) games. Significant relationships (P < .05) were observed between 30--15IFT and high-speed running during the single- (r = .72) and double- (r = .75), but not triple-contact (r = .20) game. Conclusions: There is little change in running intensity when only single contacts are performed each bout; however, when multiple contacts are performed, greater reductions in running intensity result. In addition, high-intensity-running ability is only associated with running performance when contact demands are low. [ABSTRACT FROM AUTHOR]

The second lactate threshold (LT2) has previously been associated with endurance performance; however, comparisons between sexes are lacking regarding its efficacy. The aim of this study was to compare LT2 between men and women, specifically regarding its (a) relationship with endurance performance and (b) capacity to establish training and competition intensities. Competitive male (mean ± SD: age, 27.7 ± 4.7 years; ...O2max, 59.7 ± 5.2 ml•kg•min-1; n = 10) and female (mean ± SD: age, 27.3 6 6.2 years; ...O2max, 54.5 ± 5.3 ml•kg•min-1; n = 12) cyclists and triathletes completed an incremental cycle trial to volitional fatigue (for determination of ...O2max and LT2 via the modified D-max method), a constant load (65%) exercise trial of 30 minutes at LT2 power output, and a 40-km cycle time trial. The LT2 significantly correlated with 40-km cycling performance in both men (r = -0.69 to -0.77; p < 0.01-0.05) and women (r = -0.63 to -0.75; p < 0.01-0.05). All men sustained LT2 power output for 30 minutes, compared with 82% of women. Despite LT2 reflecting a similar heart rate, ...O2, and [La-] to those elicited during a 40-km time trial in both men and women, power output at LT2 was 6% higher (p < 0.05) than mean time trial power output in women, with no significant difference in men. Based on these findings, sexspecific recommendations have been suggested in regard to the use of LT2 for establishing performance potential, prescribing endurance training intensities and setting 40-km performance intensity. [ABSTRACT FROM AUTHOR]

Recent scientific evidence supports the use of a low-volume strength–power 'resistance priming' session prior to sporting competition in an effort to enhance neuromuscular performance. Though research evidence relating to this strategy is presently limited, it has been shown to be effective in improving various measures of neuromuscular performance within 48 h. Post-activation potentiation strategies have previously been shown to enhance strength–power performance within 20 min of completing maximal or near-maximal resistance exercise. Comparably, a delayed potentiation effect has been demonstrated following 'resistance priming' at various times between 1 and 48 h in upper- and lower-body performance measures. This may have significant implications for a range of athletes when preparing for competition. Various exercise protocols have been shown to improve upper- and lower-body neuromuscular performance measures in this period. In particular, high-intensity resistance exercise through high loading (≥ 85% 1 repetition maximum) or ballistic exercise at lower loads appears to be an effective stimulus for this strategy. Although current research has identified the benefits of resistance priming to some physical qualities, many questions remain over the application of this type of session, as well as the effects that it may have on a range of specific sporting activities. The aims of this brief review are to assess the current literature examining the acute effects (1–48 h) of resistance exercise on neuromuscular performance and discuss potential mechanisms of action as well as provide directions for future research. [ABSTRACT FROM AUTHOR]

Key points: Physical activity is associated with reduced mortality rates for survivors of colorectal cancer.Acute high intensity interval exercise (HIIE) reduced colon cancer cell number in vitro and promoted increases in inflammatory cytokines immediately following exercise.This acute suppression of colon cancer cell number was transient and not observed at 120 minutes post-acute HIIE.The acute effects of exercise may constitute an important mechanism by which exercise can influence colorectal cancer outcomes. Physical activity is associated with significant reductions in colorectal cancer mortality. However, the mechanisms by which exercise mediates this anti‐oncogenic effect are not clear. In the present study, colorectal cancer survivors completed acute (n = 10) or chronic (n = 10) exercise regimes. An acute high intensity interval exercise session (HIIE; 4 × 4 min at 85–95% peak heart rate) was completed with serum samples collected at baseline, as well as 0 and 120 min post‐exercise. For the 'chronic' intervention, resting serum was sampled before and after 4 weeks (12 sessions) of HIIE. The effect of serum on colon cancer cell growth was evaluated by incubating cells (CaCo‐2 and LoVo) for up to 72 h and assessing cell number. Serum obtained immediately following HIIE, but not 120 min post‐HIIE, significantly reduced colon cancer cell number. Significant increases in serum interleukin‐6 (P = 0.023), interleukin‐8 (P = 0.036) and tumour necrosis factor‐α (P = 0.003) were found immediately following acute HIIE. At rest, short‐term HIIE training did not promote any changes in cellular growth or cytokine concentrations. The acute effects of HIIE and the cytokine flux may be important mediators of reducing colon cancer cell progression. Repetitive exposure to these acute effects may contribute to the relationship between exercise and improved colorectal cancer survival. Key points: Physical activity is associated with reduced mortality rates for survivors of colorectal cancer.Acute high intensity interval exercise (HIIE) reduced colon cancer cell number in vitro and promoted increases in inflammatory cytokines immediately following exercise.This acute suppression of colon cancer cell number was transient and not observed at 120 minutes post-acute HIIE.The acute effects of exercise may constitute an important mechanism by which exercise can influence colorectal cancer outcomes. [ABSTRACT FROM AUTHOR]

The article discusses research which investigated how three contact efforts influence running performance of athletes during small-sided rugby league games. Topics explored include the recruitment and physical evaluation of study participants, the way repeated high-intensity effort (RHIE) can affect physical performance of athletes, and the statistical analyses of data gathered such as relative distance, low-speed activity, and moderate speed running.

The article evaluates repeated high-intensity exercise performance testing for training professional rugby league and rugby union players in Queensland, Australia. The reliability and sensitivity of the test was assessed with the correlation of test performance with sprint speed and intermittent running recovery measurements. Data was analyzed using statistical methods such as analysis of variance, repeated measures statistics, and descriptive statistics.

The article presents the results of a study which investigated the influence of alternating game components upon the physiological and skill demands of rugby players. An overview of related previous research is provided, detailing heart rate increases with greater field size and smaller player numbers. Details of the experiment protocol are also presented, including use of global positioning satellites to track player movements.

The article discusses the impact of wrestling on the physiological and skills requirements in small-sided games. An overview of the game filmed to follow the number of possessions and quality of disposals along with the help of global positioning system unit is provided. The study reports that the games with wrestling show significant accelerations and repeated high-intensity efforts on body movements of the players.