Analysis of the associations between variables derived throughout velocity-based training device and jumping performances in youth soccer players: Multiple regression study

Background: It has been suggested that velocity-based training (VBT) improves real-life performance in sports, such as jumping, but studies rarely examined the associations between variables derived during VBT (VBT-variables) and jumping performances. Objective: The aim of this study was to investigate the associations between VBT-variables derived during deadlift exercise executed at different loads and anthropometric variables, and vertical and horizontal jump performance in young athletes. Methods: Seventeen youth soccer players (16-18 years old) were included. Predictors were body height, body mass, body fat percentage, and VBT-variables (force, power, and velocity) measured at different loads (45%, 55%, 65%, 75%, 85%, and 95%) of a one-repetition maximum deadlift (1RM). Criteria included tests of vertical and horizontal jumping performance. Results: The VBT-variables are more strongly correlated with horizontal jumps (Pearson's r up to .81) than vertical jumps (Pearson's r up to .75). The VBT-variables for the deadlift recorded at lower loads stronger correlated with jumping performance than the VBT-variables recorded at higher loads. Conclusions: Results of the study suggest that light-to-moderate loads (45%-65% of 1RM) maximize power output and are therefore more strongly related to jumping performance in youth athletes. Further intervention studies aimed at the improvement of jumping performances using the VBT are warranted.