Effects of Linear Versus Changes of Direction Repeated Sprints on Intermittent High Intensity Running Performance in High-level Junior Football Players over an Entire Season: A Randomized Trial
AuthorSagelv, Edvard H.; Selnæs, Ivar; Pedersen, Sigurd; Pettersen, Svein Arne; Randers, Morten B.; Welde, Boye
Methods: In total, 19 high-level male football players (16–19 years) randomly performed linear RSs or COD RSs twice a week during their competitive season over 22 weeks. Yo-Yo intermittent recovery test level 2 (Yo-Yo IR2), and 10- and 20-m sprint was assessed pre-, mid- (11 weeks), and post-intervention (22 weeks). Maximal oxygen uptake (VO2max) was assessed pre- and post-intervention.
Results: There was no interaction effect (time x group) in Yo-Yo IR2 (p = 0.36, pη 2 = 0.06) or sprint tests (10 m: p = 0.55, pη 2 = 0.04, 20 m: p = 0.28 pη 2 = 0.08), and no change differences between groups. There was a main effect of time for Yo-Yo IR2 (p = 0.002, pη 2 = 0.31) but not in sprints or VO2max.
Conclusion: Linear and COD RS exercise twice a week over 22 weeks equally improves intermittent HIR performance but does not improve sprint time or aerobic power in high-level junior football players. However, due to our two-armed intervention, we cannot exclude possible effects from other exercise components in the players’ exercise program.