Effects of Drop Height on Jump Performance in Male and Female Elite Adolescent Handball Players

Purpose : To examine the effects of drop height on drop-jump (DJ) performance and on associations between DJ and horizontal-jump/sprint performances in adolescent athletes. Methods : Male (n = 119, 2.5 0.6 y post-peak-height velocity) and female (n = 120, 2.5 0.5 y post-peak-height velocity) adolescent handball players (national level) performed DJs in randomized order using 3 drop heights (20, 35, and 50 cm). DJ performance (jump height, reactive strength index RSI) was analyzed using the Optojump Next system. In addition, correlations were computed between DJ height and RSI with standing-long-jump and 20-m linear-sprint performances. Results : Statistical analyses revealed medium-size main effects of drop height for DJ height and RSI ( P < .001, 0.63 ≤ d ≤ 0.71). Post hoc tests indicated larger DJ heights from 20 to 35 and 35 to 50 cm ( P ≤ .031, 0.33 ≤ d ≤ 0.71) and better RSI from 20- to 35-cm drop height ( P < .001, d = 0.77). No significant difference was found for RSI between 35- and 50-cm drop height. Irrespective of drop height, associations of DJ height and RSI were small with 5-m-split time (−.27 ≤ r ≤ .05), medium with 10-m-split time (−.44 ≤ r ≤ .14), and medium to large with 20-m sprint time and standing-long-jump distance (−.57 ≤ r ≤ .22). Conclusions : The present findings indicate that, irrespective of sex, 35-cm drop heights are best suited to induce rapid and powerful DJ performance (ie, RSI) during reactive strength training in elite adolescent handball players. Moreover, training-related gains in DJ performance may at least partly translate to gains in horizontal jump and longer sprint distances (ie, ≥20-m) and/or vice versa in male and female elite adolescent athletes, irrespective of drop height.