The Effect of Adding Lower-Body Plyometric Exercises to the Routine Training of TNI Soldier Trainees on Vertical Jump Height

Abstract

Background: Military training requires optimal lower-extremity muscle power, which can be reflected in vertical jump height. However, routine training does not always specifically target explosive muscle strength. Plyometric training, utilizing the stretch-shortening cycle, is known to enhance muscle power and jumping performance.

Objective: To determine the effect of additional lower extremity plyometric training on vertical jump height in military trainees.

Methods: This study was a randomized controlled experimental trial with a pre- and post-test design. The study was conducted at Kodiklatal Surabaya from June to August 2025. We randomly assigned 24 male military trainees aged 18–24 years to two groups: an intervention group (n=12), which received additional plyometric training twice per week for six weeks, and a control group (n=12), which received routine training only (waitlist control). The primary outcome was vertical jump height. We analyzed data using paired t-tests and independent t-tests.

Results: The intervention group showed a significant increase in vertical jump height from 39.88±7.71 cm to 45.97±4.40 cm (p=0.002). Post-intervention comparison between groups revealed a statistically significant difference with a moderate effect size (ES=1.15).

Conclusion: Additional plyometric training performed twice weekly for six weeks significantly improves lower extremity muscle power, as reflected by vertical jump height, in male military trainees. This training is safe, practical, and requires no specialized equipment, making it suitable for military training programs.