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Both sleep loss and exercise regulate gene expression in skeletal muscle, yet little is known about how the interaction of these stressors affects the transcriptome. The aim of this study was to investigate the effect of nine nights of sleep restriction (SR), with repeated resistance exercise (REx) sessions, on the skeletal muscle transcriptome of young, trained females. Ten healthy females aged 18–35 yr old undertook a randomized cross-over study of nine nights of SR (5 h time in bed) and normal sleep (NS; ≥7 h time in bed) with a minimum 6-wk washout. Participants completed four REx sessions per condition (days 3, 5, 7, and 9). Muscle biopsies were collected both pre- and post-REx on days 3 and 9. Gene and protein expression were assessed by RNA sequencing and Western blot, respectively. Three or nine nights of SR had no effect on the muscle transcriptome independently of exercise. However, close to 3,000 transcripts were differentially regulated (false discovery rate < 0.05) 48 h after the completion of three resistance exercise sessions in both NS and SR conditions. Only 39% of downregulated genes and 18% of upregulated genes were common between both conditions, indicating a moderating effect of SR on the response to exercise. SR and REx interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested. NEW & NOTEWORTHY: This study investigated the effect of nine nights of sleep restriction, with repeated resistance exercise sessions, on the skeletal muscle transcriptome of young, trained females. Sleep restriction and resistance exercise interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether the most important physical qualities in elite Australian male and female cricket pace bowlers change with age and phase of the cricket season. Methods: An existing longitudinal database (7 cricket seasons) of selected and routinely collected physical testing data from 103 male and 58 female elite Australian pace bowlers age 18–30 years was retrospectively analyzed. Male and female physical testing data from the isometric midthigh pull, 1-repetition-maximum bench pull, run-of-3, and countermovement jump (male only) were analyzed separately by performing linear mixed models on each of the physical qualities. Type III analysis-of-variance tests were conducted to determine if a significant effect existed within the fixed effects of age, season phase, and the age × season phase interaction. Appropriate pairwise comparisons were conducted. Results: Absolute and relative measures of force in the isometric midthigh pull and strength in the 1-repetition-maximum bench pull tests were significantly greater in older male and female pace bowlers. Older male pace bowlers demonstrated significantly faster absolute and relative best run-of-3 times. Conclusions: Most physical qualities across both male and female pace bowlers demonstrated an improvement with age. This is likely due to a training effect and would be anticipated to lead to a gradual enhancement of ball release speed, in accordance with previous research. Future research should look to investigate the relationship between the development of physical qualities and ball release speed among elite male and female pace bowlers. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the differences between selected physical attributes and ball release speed in slower and faster male and female elite pace bowlers. Methods: Twelve physical attributes and ball release speed were retrospectively analyzed from 63 male and 31 female elite pace bowlers over the course of 5 seasons. Pace bowlers were categorized as either fast (>122.9 km/h, males and >97.8 km/h, females) or slow (<122.9 km/h, males and <97.8 km/h, females) for each sex. Differences in physical attributes between slower and faster bowling groups were compared using Cohen d effect sizes. Results: Faster pace bowlers displayed differences in isometric midthigh-pull peak force (d = 0.25, males and d = 0.68, females) and relative peak force (d = 0.62, males and d = 0.77, females). Faster male pace bowlers displayed differences in relative (d = 0.61) and absolute (d = 0.39) countermovement jump heights. Faster female pace bowlers displayed differences in 1-repetition-maximum bench-pull strength (d = 0.45) and run-of-3 performance (relative average, d = 1.22; relative best, d = 1.12; average, d = 0.49; and best, d = 0.40). Conclusions: Anaerobic dominant physical attributes appear to be important in both male and female pace bowlers. The contribution of these physical attributes to ball release speed appears to differ slightly between males and females. Lower-body strength (males and females), lower-body power (males), relative anaerobic capacities (females), and upper-body strength (females) appear to distinguish between slower and faster elite pace bowlers. [ABSTRACT FROM AUTHOR]

Despite increasing popularity of cerebral palsy (CP) football (para football) worldwide, there are limited data available describing effective attacking strategies that lead to goals. The purpose of this research was to investigate the most frequent methods of ball repossession, distribution and movement patterns that successfully led to goals scored in open play of CP football. Video footage of all goals (n = 167) during the Australian National CP Football Championships in 2017 and 2018 were analysed using SportsCode software. Most goals (89.8%) were scored from open play, with the most effective mode of ball delivery identified as being direct play, of four or less passes, to create an opportunity to score. More goals were scored during the first half of games (54.9%), with a majority of goals (67.1%) scored from a region that encompasses the entire penalty area (Zone 1). The findings from the research conclude that tactically, coaches could capitalise on restarts by moving the ball quickly in four or less passes into the middle of the penalty area, to increase their chances of scoring goals in CP football. [ABSTRACT FROM AUTHOR]

Purpose: The power clean and other weightlifting movements are commonly used in the development of muscle power. However, there is a paucity of research examining the use of the hook grip (HG) in weightlifting performance. Therefore, the purpose of this study was to compare 1-repetition maximum (1RM) and kinetic, kinematic, and qualitative variables across a range of loads (75–100%) during power-clean performance with an HG and a closed grip. Methods: A total of 11 well-trained men (power-clean 1RM = 113.4 [15.9] kg, 1.34 × body mass) with at least 3 mo of HG experience volunteered to participate. Following a familiarization session, 1RM testing with the HG and closed grip were completed 5–7 d apart in a randomized order. Barbell kinetic and kinematic variables were recorded via a force platform and dual linear position transducer system. Results: All subjects had a greater 1RM with the HG than with the closed grip (P <.001, effect size [ES] = 0.43). Peak velocity (ES = 0.41–0.70), peak power (ES = 0.43–0.61), peak force (ES = 0.50–0.57), and catch height (ES = 0.40–0.96) were significantly greater (P <.05) when using the HG at all or most of the submaximal intensities. In addition, subjects reported significantly greater perceptions of grip security, power, and technical competency at submaximal but not maximal loads. Conclusions: Athletes and coaches who implement weightlifting movements in their physical preparation should adopt the HG where possible. Furthermore, researchers and sport scientists should control and report the grip type used when performing weightlifting-type movements. [ABSTRACT FROM AUTHOR]

Although plyometric training is widely used by sports coaches as a method of improving explosive power in athletes, many prescribe volumes in excess of the National Strength and Conditioning Association recommendations. The purpose of this study was to assess voluntary and evoked muscle characteristics to assess the neuromuscular impact of a high-volume bout of plyometric exercise that was non-exhaustive. Ten athletes who did not have plyometric training experience and were in their competitive season for club-level sport volunteered for the study. After at least 2 days without high-intensity activity, subjects were assessed on maximal twitch torque, time to peak torque, rate of twitch torque development, twitch half-relaxation time, rate of twitch relaxation, and voluntary activation by the interpolated twitch technique before, immediately after, and 2 hours after a high-volume plyometric training program (21 2 ground contacts). Data were analyzed by repeated-measures analysis of variance and described as mean [+ or -] SD and Cohen d. Statistically significant decrements appeared immediately after the training protocol in the total torque generated by maximal voluntary contractions (p < 0.05, d = -0.51) and twitch (p < 0.01, d = -0.92), rate of twitch torque development (p < 0.01, d = -0.77), and rate of relaxation (p < 0.01, d = -0.73). However, we did not observe any differences that remained statistically different after 2 hours. There were no significant differences observed at any time point in time to peak twitch, half-relaxation time, or voluntary activation. We conclude that high-volume piyometric training results primarily in peripheral fatigue that substantially impairs force and rate of force development. We recommend that coaches carefully monitor the volume of plyometric training sessions to avoid neuromuscular impairments that can result in suboptimal training. KEY WORDS stretch-shortening cycle, training, interpolated twitch technique, muscle activation

The purpose of this study was to investigate the importance of training leading to repetition failure in the performance of 2 different tests: 6 repetition maximum (6RM) bench press strength and 40-kg bench throw power in elite junior athletes. Subjects were 26 elite junior male basketball players (n = 12; age = 18.6 [+ or -] 0.3 years; height = 202.0 [+ or -] 11.6 cm; mass = 97.0 [+ or -] 12.9 kg; mean [+ or -] SD) and soccer players (n = 14; age = 17.4 [+ or -] 0.5 years; height = 179.0 [+ or -] 7.0 cm; mass = 75.0 [+ or -] 7.1 kg) with a history of greater than 6 months' strength training. Subjects were initially tested twice for 6RM bench press mass and 40-kg Smith machine bench throw power output (in watts) to establish retest reliability. Subjects then undertook bench press training with 3 sessions per week for 6 weeks, using equal volume programs (24 repetitions x 80-105% 6RM in 13 minutes 20 seconds). Subjects were assigned to one of two experimental groups designed either to elicit repetition failure with 4 sets of 6 repetitions every 260 seconds ([RF.sub.4x6]) or allow all repetitions to be completed with 8 sets of 3 repetitions every 113 seconds ([NF.sub.8x3]). The [RF.sub.4x6] treatment elicited substantial increases in strength (7.3 [+ or -] 2.4 kg, +9.5%, p < 0.001) and power (40.8 [+ or -] 24.1 W, +10.6%, p < 0.001), while the [NF.sub.8x3] group elicited 3.6 [+ or -] 3.0 kg (+5.0%,p < 0.005) and 25 [+ or -] 19.0 W increases (+6.8%, p < 0.001). The improvements in the [RF.sub.4x6] group were greater than those in the repetition rest group for both strength (p < 0.005) and power (p < 0.05). Bench press training that leads to repetition failure induces greater strength gains than nonfailure training in the bench press exercise for elite junior team sport athletes. KEY WORDS. Smith machine, repetition maximum, typical error of measurement, smallest worthwhile change, fatigue

he underlying biomechanical benefits of hook-grip (HG) over conventional closed-grip (CG) remain unclear. This study compared bar-path kinematics and force-time variables of the power clean (PC) performed with HG or CG. We also aimed to compared kinetic changes measured by force platform versus linear position transducer (LPT). Eleven well-trained men volunteered. Following a familiarisation session, HG, and CG 1RM conditions, were randomly completed seven days apart. System kinetics and barbell kinematics were recorded via synchronized force platform+LPT system and two-dimensional motion-capture. Statistical parametric mapping (SPM), analysis of variance, and standardised differences were utilised. The SPM cut-offs were determined via novel combination of force and displacement. No between-condition differences in normalised force-time variables of the pull or catch were detected. The first and second pull duration was similar between conditions (ES = 0.04–0.38). Conversely, catch and total PC durations were shorter at 80–95% (ES = 0.26–0.75), with the weightless phase more prolonged at 95% and 100% (ES = 0.54–0.76) with HG compared to CG. Improved timing of the turnover and catch phases appears to be the primary difference between HG and CG performance. Thus, grip type is possibly irrelevant to non-weightlifting athletes when performing submaximal catch-less derivatives.. [ABSTRACT FROM AUTHOR]