A practical complex training model for non-athletic populations: a randomized controlled trial on lower-limb power...

Explosive power training is increasingly relevant for general fitness participants. While complex training effectively enhances strength and power in athletes, its practicality and efficacy for trained non-athletes using moderate loads and minimal equipment remain unclear.

This study aimed to evaluate the effects of a practical complex training (CT) protocol-featuring moderate-load resistance and accessible plyometric exercises-on jump performance, sprint acceleration, and reactive strength in physically active young men.

Thirty trained young males (≥ 1 year of resistance and aerobic training) were randomly assigned to a complex training group (CTG, n = 15) or traditional resistance group (TRG, n = 15). Both trained 3 times/week for 6 weeks. CTG combined moderate-load resistance and basic plyometrics (e.g., squat + box jump), while TRG followed load-matched resistance-only routines. Tests included squat jump (SJ), countermovement jump (CMJ), drop jump (DJ), reactive strength index (RSI), eccentric utilization ratio (EUR), five-repetition vertical jump (5RVJ), 100-m sprint with segmental splits, standing long jump (SLJ), and 25-m sled drag. Training load was monitored using heart rate-based Training Impulse (TRIMP) and Rating of Perceived Exertion (RPE).

CTG showed no significant gains in CMJ or SJ performance (p > 0.05), but exhibited a significant improvement in EUR (p = 0.016, d = 0.76), with a notable between-group difference at post-test (p = 0.005, d = 0.92). In contrast, significant improvements were observed in DJ height (p = 0.023, r = 0.49), DJ power (interaction p = 0.0002, d = 0.51), and RSI (p = 0.031, d = 0.83). Sprint performance improved significantly in the 0-10 m (p = 0.012, r = -0.54) and 20-30 m (p = 0.016, d = 0.45) phases, with significant interaction effects observed for 100 m total time (p = 0.0035, d = 0.41). No significant changes were noted in SLJ, 25 m sled drag sprint, or 5RVJ metrics.

A CT protocol using moderate loads and basic equipment can enhance reactive strength and sprint acceleration in physically active young men, offering a practical and accessible approach for performance gains in general fitness settings.

Chinese Clinical Trial Registry (ChiCTR2500112099). Registration Date 10/11/2025 (Retrospectively registered).