Effects of Depth Jump Implementation on Sprint Performance in Collegiate and Club Sport Athletes

INTRODUCTION: Depth jumps (DJ) are popular high-intensity plyometric exercises typically reserved for highly-trained individuals. DJs cause an individual to undergo high amounts of stress during the eccentric and concentric phase. This extreme loading allows individuals to increase lower body strength and power output. Muscular strength and power have a transfer effect to sprint speed; however, few have examined if implementing DJs into training can increase sprint speed. PURPOSE: The purpose of this study was to determine if the implementation of DJs into a sprint training program would increase sprint speed more so than sprinting alone. METHODS: 5 collegiate level and 13 club level athletes participated in this study (6 males and 13 females). Subjects performed 3 maximal 40-yard sprints with 3 to 5 minutes of rest between sprints. Subjects were randomized into either a control group, a sprint training group, or a DJ group. The DJ and sprint group performed 2 training sessions/week, with both groups performing the same sprint training protocol. The DJ group had DJs of varying intensities. Following 6 weeks of implementation, subjects were retested on the 40-yard sprints in the same manner as before. RESULTS: One-way ANOVA were conducted using paired comparisons to determine significance. Significant differences were observed after implementation for the 40-yard sprint (-.24±.43s) (P<.01), 20-30yard split (-.13 ± .11s) (P<.05), and a 20-40yard split (-.20 ± .18s) (P<.01). No differences were observed between groups. The DJ group changes showed the largest effect sizes of any group in these measures; 1.12, 1.6, and 2.5 respectively. DISCUSSION: The effect sizes of the changes in sprint speed demonstrate that DJs may benefit sprint speed. It can be concluded from this study that maximal sprint speed was improved more so than acceleration due to the improvements observed from 20-30yards and 20-40yards. These indicate the maximal speed phase of sprinting. Further research is needed to determine if DJs can improve sprint performance in highly-trained athletes.