Effects of Repeated-Sprint Training Set Structure on Sprint Performance, Force-Velocity Profile, and Repeated-Sprint...

Fernández-Penedo, D, Padrón-Cabo, A, Costa, PB, and Rey, E. Effects of repeated-sprint training set structure on sprint performance, force-velocity profile, and repeated-sprint ability in youth soccer players. J Strength Cond Res XX(X): 000-000, 2026-This study compared the effects of 2 repeated-sprint training (RST) protocols of equal total volume, differing in the number of sprint repetitions per set-low (RST-LRS: 4-6 reps) vs. high (RST-HRS: 8-16 reps)-on sprint performance, horizontal force-velocity (F-V) profile, and repeated-sprint ability (RSA) in youth male soccer players. Nineteen under-16 players were randomly assigned to 1 of the protocols, with both groups completing 12 RST sessions over 6 weeks. Sprint times (5-30 m), F-V profile variables (F0, V0, Pmax, RFmax, and DRF), and RSA indices (average time, fastest time, total time, and % decrement) were assessed pre- and post-training. Significant improvements were observed in 20-m (-2.3%, p = 0.041) and 30-m (-2.1%, p = 0.026) sprint times, in Pmax (+7.2%, p = 0.037), and in RSA metrics (-3.8% to -4.7%, p < 0.01), with no significant group × time interactions for any variable. These findings indicate that both RST protocols are effective for enhancing sprint performance, maximal horizontal power, and RSA in young soccer players. From a practical perspective, coaches may select either protocol, depending on time constraints and training context, as both produced comparable adaptations when total sprint volume was equalized.