Biomechanical adaptations of kicks following vertical and single-leg plyometric training in competitive Wushu sanda athletes: implications for lower-limb explosive power and balance

Background Kicking techniques are fundamental components of performance in competitive Wushu Sanda, requiring a combination of lower-limb explosive power and dynamic balance to generate high-velocity strikes while maintaining postural stability. Plyometric training is widely recognized for enhancing neuromuscular performance; however, limited research has examined how different plyometric modalities influence the biomechanics of sport-specific kicking movements in martial arts athletes. Purpose This study aimed to investigate the biomechanical adaptations of kicking performance following vertical plyometric training (VPT) and single-leg plyometric training (SLPT) in competitive Wushu Sanda athletes. Methods Thirty-six competitive Wushu Sanda athletes (18–25 years) were randomly assigned to three groups: VPT (n = 12), SLPT (n = 12), and a control group (CG; n = 12). The intervention lasted eight weeks with training sessions conducted three times per week. Biomechanical assessments were performed before and after the intervention using a three-dimensional motion capture system (250 Hz) and a force platform (1000 Hz). Key variables included peak ground reaction force (GRF), rate of force development (RFD), kick velocity, hip and knee angular velocities, and center of pressure (COP) displacement. Data were analyzed using two-way repeated-measures ANOVA (Group × Time), with significance set at p < 0.05. Results Significant group × time interactions were observed for peak GRF (p < 0.001), RFD (p = 0.001), kick velocity (p = 0.001), knee angular velocity (p = 0.003), and COP displacement (p < 0.001). The VPT group demonstrated greater improvements in explosive power and kick velocity, whereas the SLPT group exhibited superior improvements in dynamic balance and inter-limb stability. Conclusion Both plyometric training modalities significantly enhanced kicking biomechanics in Wushu Sanda athletes, but produced distinct neuromuscular adaptations. VPT was more effective for improving explosive power and kicking velocity, while SLPT better enhanced dynamic balance. Integrating both modalities may optimize sport-specific performance in martial arts athletes.