Effect of Plyometrics and Whole Body Vibration on Vertical Jump Height

Abstract

PURPOSE: the purpose of the study was to analyze the effect of plyometric and whole body vibration training methods on vertical jump height in athletes. METHODS: A meta-analysis was performed where the inclusion criteria for the studies were: (a) only athletic population, (b) active control group, (c) only one experimental intervention, (d) statistical data necessary to calculate effect sizes (ES). Hedge´s standardized mean difference ES was calculated for each result; then, ESs pooled using random-effects models. On-overlapping 95% confidence intervals (CI 95%) were considered statistically significant. Heterogeneity was assessed using Q and I2, while funnel plots and Egger´s regression test were used to assess small-study effects (potential bias). RESULTS: One hundred and fifteen effect sizes were calculated from 36 studies. Global effect sizes (ES) were statistically different from zero in both training methods. Plyometric training had an ES = 1.046 (CI 95% = 0.82 to 1.27, p <0.001) and the control group an ES = 0.032 (CI 95% =-0.12 to 0.18, p= 0.73). The ES for the experimental group in the whole body vibration training method was 0.652 (CI 95% =0.3 to 1.0, p= 0.001) and the control group an ES= 0.038 (CI 95% =0.3 to 1.0, p=0.75. ESs were correlated to age (r= 0.454, p=0.002), number of weeks of training (r: 0.309, p= 0.039), final number of sessions per week (r=0.348, p=0.019), final duration of sessions (r= 0.619, p: 0.014), initial series of exercises (r=0.572, p= <0.00), final series of exercises (r= 0.601, p= <0.00) and initial number of jumps per session (r= 0.633, p= 0.027) in the plyometric experimental method. No significant associations between ESs and moderator variables were observed in the whole body vibration method. CONCLUSIONS: The overall results showed a statistically significant improvement on the vertical jump height of athletes when plyometrics or whole body vibration were used as training methods.