Effects of conditioning hops on drop jump and sprint performance: a randomized crossover pilot study in elite athletes.

Jakob Kümmel,Markus Gruber,Julian Bergmann,Andreas Kramer,Olaf Prieske,Urs Granacher

doi:10.1186/s13102-016-0027-z

Jakob Kümmel, Markus Gruber + Show 4 more

Open Access

https://doi.org/10.1186/s13102-016-0027-z

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Abstract

BackgroundIt has previously been shown that conditioning activities consisting of repetitive hops have the potential to induce better drop jump (DJ) performance in recreationally active individuals. In the present pilot study, we investigated whether repetitive conditioning hops can also increase reactive jump and sprint performance in sprint-trained elite athletes competing at an international level.MethodsJump and sprint performances of 5 athletes were randomly assessed under 2 conditions. The control condition (CON) comprised 8 DJs and 4 trials of 30-m sprints. The intervention condition (HOP) consisted of 10 maximal repetitive two-legged hops that were conducted 10 s prior to each single DJ and sprint trial. DJ performance was analyzed using a one-dimensional ground reaction force plate. Step length (SL), contact time (CT), and sprint time (ST) during the 30-m sprints were recorded using an opto-electronic measurement system.ResultsFollowing the conditioning activity, DJ height and external DJ peak power were both significantly increased by 11 % compared to the control condition. All other variables did not show any significant differences between HOP and CON.ConclusionsIn the present pilot study, we were able to demonstrate large improvements in DJ performance even in sprint-trained elite athletes following a conditioning activity consisting of maximal two-legged repetitive hops. This strengthens the hypothesis that plyometric conditioning exercises can induce performance enhancements in elite athletes that are even greater than those observed in recreationally active athletes.. In addition, it appears that the transfer of these effects to other stretch-shortening cycle activities is limited, as we did not observe any changes in sprint performance following the plyometric conditioning activity.

Highlights

It has previously been shown that conditioning activities consisting of repetitive hops have the potential to induce better drop jump (DJ) performance in recreationally active individuals
The Wilcoxon signed-rank test for paired samples revealed a significant increase in mean jump height (11 %; p < 0.05) in the hops conditions (HOP) (0.35 m) compared to the CON (0.31 m) condition (ICCJH: 0.98, p < 0.01)
The mean rebound jump height (JH) over the 8 DJs increased for each single athlete in the HOP compared to the CON condition

Summary

Introduction

It has previously been shown that conditioning activities consisting of repetitive hops have the potential to induce better drop jump (DJ) performance in recreationally active individuals. The muscle’s capability of generating high forces is dependent on its contractile history and can be acutely enhanced following voluntary contractions at maximal or near-maximal intensities [1]. These short-term enhancements can be observed on a behavioral and mechanistic level. A few studies used plyometric exercise as a conditioning stimulus in order to increase countermovement jump (CMJ) [3,4,5,6,7,8,9,10,11], DJ [8, 12, 13], sprint [6, 11] and back squat performance [14]. Terzis and colleagues for example have shown that 5 consecutive DJs significantly improved immediate following squat

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