Moran, J, Clark, CCT, Ramirez-Campillo, R, Davies, MJ, and Drury, B. A meta-analysis of plyometric training in female youth: its efficacy and shortcomings in the literature. J Strength Cond Res XX(X): 000-000, 2018-This meta-analysis characterized female youths' adaptability to plyometric training (PT). A second objective was to highlight the limitations of the body of literature with a view to informing future research. Fourteen studies were included in the final analysis. The effect size (ES = Hedges' g) for the main effect of vertical jump performance was "small" (ES = 0.57, 95% confidence interval: 0.21-0.93). Effect sizes were larger in younger (<15 years; ES = 0.78 [0.25-1.30] vs. 0.31 [-0.18 to 0.80]), shorter (<163 cm; ES = 1.03 [0.38-1.68] vs. 0.25 [-0.20 to 0.70]), and lighter (<54 kg; ES = 1.14 [0.39-1.89] vs. 0.26 [-0.15 to 0.67]) participants. Programming variables seemed to influence adaptive responses with larger effects in interventions which were longer (8 weeks; ES = 1.04 [0.35-1.72] vs. 0.24 [-0.11 to 0.59]), had greater weekly training frequency (>2; ES = 1.22 [0.18-2.25] vs. 0.37 [0.02-0.71]), and whose sessions were of longer duration (≥30 minutes ES = 1.16 [0.14-2.17] vs. 0.33 [0.03-0.63]). More than 16 sessions per program (0.85 [0.18-1.51]) was more effective than exactly 16 sessions (0.46 [0.08-0.84]) which, in turn, was more effective than less than 16 (0.37 [-0.44 to 1.17]). These findings can inform the prescription of PT in female youth.

Resistance training is effective in female youth. These findings can be used to inform the prescription of RT in female youth.

Background: Small sided games (SSGs) have been suggested as a viable alternative to conventional endurance training (CET) to enhance endurance performance in youth soccer players. This has important implications for long-term athlete development because it suggests that players can increase aerobic endurance through activities that closely resemble their sport of choice. Objectives: This meta-analysis compared male youth soccer players' adaptability to SSG vs. CET and sought to establish exercise prescription guidelines for this population. Data sources: The data sources utilised were Google Scholar, PubMed and Microsoft Academic. Study eligibility criteria: Studies were eligible for inclusion if interventions were carried out in male soccer players (<18 years) and compared the effects of SSG and CET on aerobic endurance performance. We defined SSG as "modified [soccer] games played on reduced pitch areas, often using adapted rules and involving a smaller number of players than traditional games". We defined CET as continuous running or extensive interval training consisting of work durations >3 mins. Study appraisal and synthesis methods: The inverse-variance random effects model for meta-analyses was used because it allocates a proportionate weight to trials based on the size of their individual standard errors and facilitates analysis whilst accounting for heterogeneity across studies. Effect sizes (ES) were represented by the standardised mean difference and presented alongside 95% confidence intervals (CI). Results: Seven studies were included in this meta-analysis. Both modes of training were effective in increasing endurance performance. Within-mode ESs were both of moderate magnitude (SSG: 0.82 [95% confidence interval [

Purpose: This study examined the effects of a 6-week Nordic hamstring exercise (NHE) program in youth male soccer players of less mature (pre–peak height velocity [PHV]) or more mature (mid/post-PHV) status. Methods: Forty-eight participants were separated into pre-PHV (11.0 [0.9] y) or mid/post-PHV (13.9 [1.1]) groups and further divided into experimental (EXP) and control groups with eccentric hamstring strength assessed (NordBord) both before and after the training program. Participants in the EXP groups completed a periodized NHE program performed once or twice weekly over a 6-week period. Results: The NHE program resulted in moderate and small increases in relative eccentric hamstring strength (in newtons per kilogram) in the pre-PHV EXP (d = 0.83 [0.03–1.68]) and mid-PHV EXP (d = 0.53 [−0.06 to 1.12]) groups, respectively. Moderate increases in the same measure were also seen in the between-groups analyses in the pre-PHV (d = 1.03 [0.23–1.84]) and mid-PHV (d = 0.87 [0.22–1.51]) groups, with a greater effect observed in the former. Conclusion: The results from this study demonstrate that a 6-week NHE program can improve eccentric hamstring strength in male youth soccer players, with less-mature players achieving mostly greater benefits. The findings from this study can aid in the training prescription of NHE in youth male soccer players.

No abstract

This study examined the accuracy of different velocity-based methods in the prediction of bench press and squat one-repetition maximum (1RM) in female athletes. Seventeen trained females (age 17.8 ± 1.3 years) performed an incremental loading test to 1RM on bench press and squat with the mean velocity being recorded. The 1RM was estimated from the load–velocity relationship using the multiple- (8 loads) and two-point (2 loads) methods and group and individual minimum velocity thresholds (MVT). No significant effect of method, MVT or interaction was observed for the two exercises (p > 0.05). For bench press and squat, all prediction methods demonstrated very large to nearly perfect correlations with respect to the actual 1RM (r range = 0.76 to 0.97). The absolute error (range = 2.1 to 3.8 kg) for bench press demonstrated low errors that were independent of the method and MVT used. For squat, the favorable group MVT errors for the multiple- and two-point methods (absolute error = 7.8 and 9.7 kg, respectively) were greater than the individual MVT errors (absolute error = 4.9 and 6.3 kg, respectively). The 1RM can be accurately predicted from the load–velocity relationship in trained females, with the two-point method offering a quick and less fatiguing alternative to the multiple-point method.

There is no 'one site fits all' approach to the selection of accelerometer site location or analytical technique. Research design and focus should always inform the most suitable location of attachment, and should be driven by the type of activity being characterized.

The purpose of this study was to investigate the between-and within-sex differences in actual and perceived locomotor and object control skills in children (8-10 year). All participants (58 children (29 boys; 9.5 ± 0.6 years; 1.44 ± 0.09 m; 39.6 ± 9.5 kg; body mass index; 18.8 ± 3.1 kg·m 2 )) completed the Test of Gross Motor Development (2nd edition) and the Pictorial Scale of Perceived Movement Skill Competence for Young Children. Between-and within-sex differences were assessed using independent and paired samples t-tests, respectively. For all tests, effect sizes and Bayes factors were calculated. There were significant differences (p < 0.001) between sexes for perceived locomotor and perceived object control skills (boys > girls), with Bayes factors extremely in favour of the alternate hypothesis ( BF : 55,344 and 460, respectively). A significant difference (p < 0.001) was found between girls' actual and perceived locomotor skills (d = −0.88; 95% confidence interval: −0.46 to −1.34), with Bayes factors extremely in favour of the alternate hypothesis ( BF : 483). A significant difference (p < 0.001) was found between boys' actual and perceived object control skills (d = 0.69; 95% CI: 0.2 to 1.12), with Bayes factors very strongly in favour of the alternate hypothesis ( BF : 41). These findings suggest that there exists an issue of non-veridicality between actual and perceived motor competence skills, and their subsets, and a sex-mediated discord in children (8-10 years).