The effect of repeated-sprint training on performance outcomes in youth athletes: a meta-analysis

Objective: This study aimed to conduct a meta-analysis to examine the effects of repeated sprint training (RST) on performance outcomes in youth athletes. Methods: tests, and a sensitivity analysis was conducted when necessary. Result: The study analyzed eight studies involving 193 participants aged 13 to 18 across various sports. RST protocols varied in terms of sets, repetitions, and intensities, while the control groups (CG) followed standard curricula. Compared to CG, significant improvements were observed in 10-meter and 20-meter sprints (effect size: 1.01, 95% CI [0.52-1.50]; 0.80, [0.09, 1.52]), change-of-direction (COD) performance (effect size: 0.60, [0.14, 1.06]), and best repeated-sprint ability (RSAbest) with RST (effect size: 0.48, [0.07, 0.89]). However, sensitivity analysis indicated that the pooled 20-m sprint effect became non-significant when the study by Uthoff et al. (2020: DOI 10.1519/JSC.0000000000002914) was excluded. No significant differences were found in vertical jump performance, RSAmean, RSAdec, or maximum aerobic performance. Conclusion: RST enhances 10-m sprint, COD, and RSAbest in youth athletes. Evidence for 20-m sprint improvements should be interpreted cautiously because the pooled effect was sensitive to exclusion of a single study. RST shows limited effects on vertical jump performance, RSAmean, RSAdec, and aerobic capacity; thus, complementary training may be required. Future studies should refine RST protocols, standardize testing, and report maturation to enable maturity-stratified analyses and improve comparability across studies.