Dynamic Warm-up Duration Does Not Influence Vertical Jump Performance

Abstract

Warm-up prepares the body for activity and minimizes injury risk while not hindering performance. However, the optimal parameters for a warm-up have yet to be defined. This study sought to determine how dynamic warm-up duration (5 vs. 10 minutes) influences vertical jump height and muscle strength. Twelve healthy adults (n=6 female, age: 21.5 ± 3.4 years; height:1.6 ± 0.1 m, mass: 58.2 ± 10.4 kg; n=6 male, age: 23.0 ± 0.9 years, height: 1.8 ± 0.1 m, mass: 91.0 ± 13.4 kg) completed 3 sessions: baseline and the dynamic warmups, each separated by 1 week. Warm-up order was randomized. Baseline and post-warm-up testing included vertical jump and quadriceps and hamstrings strength (normalized to body mass) assessment. The short warm-up consisted of dynamic stretches and a plyometric circuit performed for 5-minutes. The long warmup was identical to the short, except it was performed for 10-minutes. Heart rate and rating of perceived exertion were recorded before and after each warm-up. Repeated measures ANCOVAs with sex as a covariate determined differences in vertical jump and normalized muscle strength over time. Heart rate was analyzed using repeated measures ANOVAs and Wilcoxon signed ranks tests examined changes in rating of perceived exertion over time. Males jumped higher than females (P<0.001); however, vertical jump height did not differ between protocols (P=0.082). Males had stronger quadriceps than females at baseline (P=0.017) but not following the short (P=0.091) or long (P=0.729) protocols. Quadriceps strength was greater at baseline (P<0.001) while hamstrings was lower (P=0.004). Heart rate (P<0.001) and rating of perceived exertion (P=0.002) were greater following both warm-ups compared to baseline. Warm-up did not improve vertical jump performance. Quadriceps strength did begin to decline; therefore, care should be taken when designing a dynamic warm-up in order not to impair subsequent activity performance.