Individualized responses to velocity-based versus percentage-based resistance training in combat sports athletes: the influence of baseline characteristics

Background Traditional percentage-based resistance training (PBRT) is a cornerstone of strength development, but its fixed nature may not account for daily fluctuations in athlete readiness. Velocity-based resistance training (VBRT) has been proposed as a superior alternative for power development due to its auto-regulatory capabilities, but its efficacy in highly trained combat sports athletes remains contested. Objective This study aimed to compare the effects of velocity-based resistance training (VBRT) and percentage-based resistance training (PBRT) on upper limb strength, general power, and sport-specific power in combat sports athletes, and to explore individualized training responses. Methods A randomized parallel-group controlled trial was conducted, recruiting 24 male university combat sports athletes (age: 21.5 ± 2.1 years; training experience: 4.8 ± 1.5 years; baseline bench press one-repetition maximum (1RM): 95.4 ± 10.2 kg). Participants were randomly assigned to either a VBRT group ( n = 12) or a PBRT group ( n = 12) for an 8-week bench press intervention. Pre- and post-intervention tests included bench press 1RM, medicine ball throws, and power in the Seoi-nage (shoulder throw). Results A 2 × 2 mixed-model analysis of variance (ANOVA) revealed that while both groups significantly improved in most metrics, the PBRT group demonstrated significantly greater improvements in several key areas. Significant Group × Time interactions were found favoring the PBRT group for 4kg medicine ball velocity ( p < .001), power ( p = .012), and distance ( p = .020), as well as for sport-specific power in both the left ( p < .001) and right ( p = .018) Seoi-nage. Crucially, at post-test, the PBRT group’s left Seoi-nage power was significantly higher than the VBRT group’s ( p = .035). Exploratory cluster analysis identified three distinct athlete subgroups, and PBRT elicited superior or comparable training adaptations across all of them. Conclusion For the cohort of university-level combat sports athletes in this study, PBRT was a more effective training methodology than VBRT for enhancing both general and sport-specific power. These findings challenge the assumption of VBRT’s universal superiority for power development and highlight the continued efficacy and robustness of traditional PBRT for strength and conditioning in this population.