Abstract
OBJECTIVES: This randomized controlled trial compared the effects of velocity-based complex training (VBCT) and traditional complex training (TCT) on lower-limb maximal strength and explosive performance in male volleyball athletes during the competitive season. METHODS: Thirty athletes were randomly assigned to VBCT (n = 10), TCT (n = 10), or a control group (CON, n = 10). The VBCT and TCT groups trained twice weekly for eight weeks. Pre- and post-intervention assessments included 1RM squat, countermovement jump (CMJ), squat jump (SJ), eccentric utilization rate (EUR), and standing long jump (SLJ). RESULTS: Both VBCT and TCT improved 1RM squat, CMJ, SJ, and SLJ, whereas only VBCT improved EUR (p < 0.01). Post-intervention, VBCT demonstrated significantly greater improvements than TCT in CMJ (VBCT: η² = 0.65; TCT: η² = 0.41) and EUR (VBCT: η² = 0.45; TCT: η² = 0.07) (p < 0.05). Training intensity did not differ between groups (p > 0.05), but VBCT showed lower training volume, fewer repetitions, and lower rating of perceived exertion, while exhibiting higher mean concentric velocity for each repetition within squat sets compared with TCT (p < 0.01). CONCLUSIONS: VBCT resulted in greater improvements in CMJ and EUR, while its effects on 1RM, SJ, and SLJ were similar to TCT. With lower volume and fatigue, VBCT may be a more efficient strategy for enhancing lower-limb strength and explosiveness during the competitive season. TRIAL REGISTRATION: This study was registered at the Chinese Clinical Trial Registry ( www.chictr.org.cn ) with the following details: Registration Number: ChiCTR2400093910. Registration Date: 13/12/2024.