# Effects of Weighted Vest Sprint Training on Mid-Acceleration and Reactive Strength in Post-PHV Soccer Players

## TL;DR

This study explores how wearing a weighted vest during sprints affects soccer players' speed and jumping ability after they've reached their growth spurt.

## Contribution

The study introduces an individualized weighted vest training program for post-PHV soccer players and evaluates its impact on mid-acceleration and reactive strength.

## Key findings

- Weighted vest training showed greater improvements in 10 m sprint performance and RSI-modified.
- Effects were not statistically significant after adjusting for multiple comparisons.
- Maturity offset did not influence the training outcomes.

## Abstract

Background: This study examined the effects of an individualized weighted vest sprint training program on sprint performance and countermovement jump (CMJ) outcomes in post-peak height velocity (PHV) male youth soccer players while accounting for maturation status. Methods: Fifty players (mean age 17.76 ± 0.95 years) were randomly assigned to a weighted vest sprint group (WVG; n = 25) or a traditional unloaded sprint group (TS; n = 25). Sprint performance (5, 10, 20, and 30 m) and CMJ-derived variables (jump height, peak power output, reactive strength index modified (RSI-modified), and eccentric rate of force development) were assessed before and after an 11-week intervention performed twice weekly, with the WVG completing sprint drills while wearing a weighted vest (~11% body mass). Results: Weighted vest sprint training produced greater improvements in 10 m sprint performance and RSI-modified (d = 1.37 and 1.55, respectively). However, after Benjamini–Hochberg adjustment for multiple comparisons, the effects were no longer statistically significant and should therefore be interpreted with caution. Maturity offset did not meaningfully moderate training-induced adaptations. Conclusions: These findings suggest that weighted vest sprint training may provide potential benefits for mid-acceleration performance and reactive strength in post-PHV youth soccer players, although the magnitude of these effects remains uncertain.