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Mike Stoker, Ian Maynard, Joanne Butt, Kate Hays and Paul Hughes

In previous research, multiple demands and consequences were manipulated simultaneously to examine methods for pressure training. Building on literature, in this study a single demand or consequence stressor was manipulated in isolation. Specifically, in a matched within-subject design, 6 international shooters (mean age 28.67 yr) performed a shooting task while exposed to a single demand (task, performer, environmental) or consequence (reward, forfeit, judgment) stressor. Perceived pressure, anxiety (intensity and direction), and performance were measured. Compared with baseline, manipulating demands did not affect pressure or anxiety. In contrast, pressure and cognitive anxiety significantly increased when judgment or forfeit consequence stressors were introduced. Thus, the findings lack support for manipulating demands but strongly support introducing consequences when pressure training. Compared with baseline, the judgment stressor also created debilitative anxiety. Hence, in terms of introducing a single stressor, judgment appeared most impactful and may be most effective for certain athlete populations.

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Seung Ho Chang, Kyungun Kim, Jihyun Lee and Sukho Lee

Background: Children and youths from low-income families and certain ethnic minority groups show high levels of risk and vulnerability to physical inactivity. The aim of this review was to examine the effectiveness of interventions to increase physical activity (PA) in children and youths from low-income and ethnic minority (LIEM) families. Methods: Eight databases were systematically searched for PA interventions for LIEM children and youths. Twenty-six studies were included in the analyses. Effect sizes (ESs) were calculated using a random-effects model. The ESs were computed using Hedges g with 95% confidence interval. Results: There were small to medium effects of interventions on PA in LIEM children and youth (Q = 1499.193, df = 30, P < .05; I 2 = 97.999). Analyses on the moderator variables showed that ES for participants aged 9–12 years (ES = 0.542, P = .01); intervention length less than 13 weeks (ES = 0.561, P = .01); specialists as the intervention agent (ES = 0.680, P < .05); interventions without technology (ES = 0.363, P = .02); and interventions with a behavioral modification component (ES = 0.336, P = .03) were significantly different from zero. Conclusion: PA intervention can be an effective strategy to increase PA for LIEM children and youths.

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Dana M. Lis and Keith Baar

Nutritional strategies to improve connective tissue collagen synthesis have garnered significant interest, although the scientific validity of these interventions lags behind their hype. This study was designed to determine the effects of three forms of collagen on N-terminal peptide of procollagen and serum amino acid levels. A total of 10 recreationally active males completed a randomized double-blinded crossover design study consuming either placebo or 15 g of vitamin C–enriched gelatin or hydrolyzed collagen (HC), or gummy containing equal parts of gelatin and HC. Supplements were consumed 1 hr before 6 min of jump rope. Blood samples were collected immediately prior to supplement consumption and 4 hr after jump rope. A subset of blood samples (n = 4) was collected for amino acid analysis 1 hr after ingestion. Consumption of an equivalent dose of each supplement increased amino acids in the circulation similarly across all interventions. N-terminal peptide of procollagen levels tended to increase ∼20% from baseline in the gelatin and HC interventions but not the placebo or gummy. These results suggest that vitamin C–enriched gelatin and HC supplementation may improve collagen synthesis when taken 1 hr prior to exercise. However, large variability was observed, which precluded significance for any treatment.

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Adam D. Osmond, Dean J. Directo, Marcus L. Elam, Gabriela Juache, Vince C. Kreipke, Desiree E. Saralegui, Robert Wildman, Michael Wong and Edward Jo

Context: Of the 3 branched-chain amino acids (BCAA), leucine has arguably received the most attribution for the role of BCAA supplementation in alleviating symptoms of exercise-induced muscle damage and facilitation of acute performance recovery. Purpose: To examine whether enrichment of a standard BCAA supplement with additional leucine or a standalone leucine (LEU) supplement differentially affects exercise-induced muscle damage and performance recovery compared with a standard BCAA supplement. Methods: A total of 22 recreationally active male and female subjects were recruited and assigned to consume a BCAA, leucine-enriched BCAA (LBCAA), or LEU supplement for 11 d. On the eighth day, subjects performed eccentric-based resistance exercise (ECRE). Lower-body mean average and peak power, plasma creatine kinase, soreness, and pain threshold were measured before and 24, 48, and 72 h after ECRE. Results: LEU showed decreased mean average power (P = .02) and mean peak power (P = .01) from baseline to 48 h post-ECRE, whereas LBCAA and BCAA only trended toward a reduction at 24 hours post-ECRE. At 48 h post-ECRE, BCAA showed greater recovery of mean peak power than LEU (P = .04). At 24 h post-ECRE, LEU demonstrated a greater increase in plasma creatine kinase from baseline than BCAA (P = .04). Area under the curve for creatine kinase was greater in LEU than BCAA (P = .02), whereas BCAA and LBCAA did not differ. Only LEU demonstrated increased soreness during rest and under muscular tension at 24 and 48 h post-ECRE (P < .05). Conclusions: LBCAA failed to afford any advantages over a standard BCAA supplement for postexercise muscle recovery, whereas a LEU supplement was comparatively ineffective.

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David Rodríguez-Osorio, Oliver Gonzalo-Skok and Fernando Pareja-Blanco

Purpose: To compare the effects of resisted change-of-direction (COD) movements, using several relative loads, on soccer players’ physical performance. Methods: Fifty-four male soccer players were randomly assigned to 1 of the following 3 groups, which differed only in the magnitude of the external load used during the COD training: COD training without external load (COD-0; n = 16), COD training with a 12.5% body-mass external load (COD-12.5; n = 19), and COD training with a 50% body-mass external load (COD-50; n = 19). Participants performed the specific COD training twice per week for 6 wk. Before and after the training period, a battery of tests was completed: countermovement jump, 30-m running sprint (time in 10 m [T10], 20 m [T20], and 30 m [T30]), L-run test, and V-cut test. Results: Within-group comparisons showed substantial improvements in countermovement jump and T10 (likely) in COD-0, whereas countermovement jump, T10, and T20 were substantially enhanced (possibly to likely) in COD-50. COD-12.5 induced substantial improvements in all analyzed variables (likely to most likely). Between-groups comparisons showed better effects on all analyzed variables for COD-12.5 than for COD-0 (possibly to very likely), whereas COD-50 only showed possibly better effects than COD-0 on T10. In addition, COD-12.5 induced a better effect on L-run and V-cut tests than COD-50 (possibly to likely). Conclusions: These results indicate that COD training, especially moderate load (12.5% body mass) resisted COD training, may have a positive effect on COD skills, running sprint performance, and jumping ability in young soccer players.

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Florence Lebrun, Áine MacNamara, Dave Collins and Sheelagh Rodgers

Little is known about the coping strategies used by elite athletes suffering from mental health issues. Therefore, this study examined coping strategies implemented by elite athletes facing clinical depression. Semi-structured interviews were conducted with four elite athletes and analysed using Interpretative Phenomenological Analysis (IPA). Results present a broad picture of how elite athletes tried to cope with depression using a range of coping strategies. Among the different strategies highlighted, talking, seeking professional help and social support were particularly emphasized by the participants. Surprisingly, however, only one participant reported transferring the skills and strategies learned on her way to the top to many other aspects of her everyday life such as coping with her depression. Findings, therefore, suggest that athletes should be encouraged to transfer and make the most of the skills learned throughout their sport career to deal with their daily life. Future research perspectives and implications are discussed.

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Sarah G. Sanders, Elizabeth Yakes Jimenez, Natalie H. Cole, Alena Kuhlemeier, Grace L. McCauley, M. Lee Van Horn and Alberta S. Kong

Background: Reports of physical activity (PA) measured via wrist-worn accelerometers in adolescents are limited. This study describes PA levels in adolescents at baseline of an obesity prevention and weight management trial. Methods: Adolescents (n = 930) at 8 high schools wore an accelerometer for 7 days, with average acceleration values of <50 mg, >150 mg, and >500 mg categorized as sedentary, moderate, and vigorous PA, respectively. In a 3-level mixed-effects generalized linear model, PA was regressed on sex, weight status, and day of week. Daily PA was nested within students, and students within schools, with random effects included for both. Results: Adolescents accumulated a median of 40 minutes daily of moderate to vigorous PA (MVPA). MVPA was significantly different for teens with obesity versus teens with normal weight (−5.4 min/d, P = .03); boys versus girls (16.3 min/d, P < .001); and Sundays versus midweek (−16.6 min/d, P < .001). Average sedentary time increased on weekends (Saturday: 19.1 min/d, P < .001; Sunday: 44.8 min, P < .001) relative to midweek but did not differ by sex or weight status. Conclusions: Interventions to increase PA in adolescents may benefit from focusing on increasing weekend PA and increasing MVPA in girls.

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Carolina F. Wilke, Felipe Augusto P. Fernandes, Flávio Vinícius C. Martins, Anísio M. Lacerda, Fabio Y. Nakamura, Samuel P. Wanner and Rob Duffield

Purpose : To investigate the existence of faster vs slower recovery profiles in futsal and factors distinguishing them. Methods: 22 male futsal players were evaluated in countermovement jump, 10-m sprint, creatine kinase, total quality of recovery (TQR), and Brunel Mood Scale (fatigue and vigor) before and immediately and 3, 24, and 48 h posttraining. Hierarchical cluster analysis allocated players to different recovery profiles using the area under the curve (AUC) of the percentage differences from baseline. One-way ANOVA compared the time course of each variable and players’ characteristics between clusters. Results : Three clusters were identified and labeled faster recovery (FR), slower physiological recovery (SLphy), and slower perceptual recovery (SLperc). FR presented better AUC in 10-m sprint than SLphy (P = .001) and SLperc (P = .008), as well as better TQR SLphy (P = .018) and SLperc (P = .026). SLperc showed better AUC in countermovement jump than SLphy (P = .014) but presented worse fatigue AUC than SLphy (P = .014) and FR (P = .008). AUC of creatine kinase was worse in SLphy than in FR (P = .001) and SLperc (P < .001). The SLphy players were younger than SLperc players (P = .027), whereas FR were slower 10-m sprinters than SLphy players (P = .003) and SLperc (P = .013) and tended to have higher maximal oxygen consumption than SLphy (effect size =1.13). Conclusion : Different posttraining recovery profiles exist in futsal players, possibly influenced by their physical abilities and age/experience.

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Sarah J. Wherry, Cheryl Der Ananian and Pamela D. Swan

Background: This study evaluated the feasibility and effectiveness of a home-based exercise intervention using the Wii Fit Plus®. Methods: A randomized, controlled trial of 24 women (age 53.6 [5.4] y) was used to assess compliance and changes in balance over 12 weeks. Balance was measured via the Berg Balance Scale and Frailty and Injuries: Cooperative Studies of Intervention Techniques-4 Scale at baseline and week 6 and week 12. Participant compliance to the intervention was captured via paper logs and the electronic record collected by the Wii Fit Plus®. Results: Participants in the intervention group were 95% compliant based on electronic records. There were no significant differences between groups for total score on either balance scale. There was a significant group × time interaction in favor of the intervention for maximum velocity y (P < .05), average velocity (P < .05), and was trending for maximum velocity x (P = .05) in the tandem step, eyes closed position. Conclusions: The results suggest that the Wii Fit Plus® is appropriate for home-based interventions in middle-aged women. Modest improvements in balance indicate that this may be an effective means to improve or maintain balance in older women. More research is needed to determine compliance and benefits to reducing fall risk in durations exceeding 12 weeks.