Effects of 12-week full body resistance exercise on vertical jumping with and without military equipment in Slovenian Armed Forces

Introduction Jumping ability is one of the most important physical qualities in military personnel. Previous training intervention studies have shown equivocal effects on jumping ability. In this study, we assessed the effect of a 12-week resistance exercise programme on countermovement jump (CMJ) performance with and without military equipment. Methods Ninety-six members of the Slovenian Armed Forces (age range 20–47 years) were allocated to the intervention (n=65) and the control (n=32) group. The intervention group performed 2 sessions of full body resistance exercise per week for 12 weeks, while the control group continued with their regular training routine. Before and after the intervention, CMJ assessment using force plates was conducted with and without military equipment. Results CMJ testing with and without equipment both exhibited high to excellent relative and absolute reliability. The intervention elicited statistically significant (p=0.011–0.026; η2=0.05–0.06), but small improvements in CMJ height when performed without equipment (from 28.2±3.8cm to 29.5±3.3cm) and with equipment (from 25.3±3.7cm to 27.1±6.1). Other variables showed even smaller or trivial changes. Conclusions This study suggests that CMJ with equipment could be a reliable tool to assess jumping performance specific to requirements of military work, which would increase the ecological validity of the testing. The present structured full-body training intervention showed modest improvements in jumping ability in both testing conditions. Trial registration number NCT034154