Kinematic and kinetic differences between lead and rear straight punches in elite boxers: bilateral asymmetry and training implications

BACKGROUND: In boxing, differences in technical efficacy are commonly observed between lead-hand and rear-hand straight punches, as well as in limb asymmetry. However, systematic analyses of the kinematic and kinetic characteristics of lead- and rear-hand straight punches remain limited. In this study, we elucidated differences in kinematic and kinetic performance between lead-hand (non-dominant) and rear-hand (dominant) straight punches in boxers, characterized limb asymmetry, and provide evidence-based guidance for the scientific training of straight punch techniques. METHODS: Seventeen male boxers (orthodox stance, right-handed; height: 175.25 ± 7.81 cm; body mass: 66.06 ± 2.77 kg) performed lead- and rear-hand straight punches with maximal effort. Data were synchronously collected using a Vicon infrared motion capture system, two Kistler force plates, and one force target. Key variables included movement completion time, trunk rotational range of motion (ROM), peak forward rotational angular velocity (power phase), peak reverse rotational angular velocity (loading phase), peak punch velocity, impact velocity, and peak force. RESULTS: For movement speed, lead-hand punches exhibited significantly shorter completion times than rear-hand punches (p < 0.01), indicating greater speed in the lead-hand technique. Trunk rotation metrics revealed a significantly greater ROM in rear-hand punches (p < 0.01). Rear-hand punches also exhibited a higher peak forward rotational angular velocity (p < 0.01). No significant difference was observed in peak reverse rotational angular velocity (p > 0.05). With regard to punching efficacy, rear-hand punches produced a significantly higher peak force, peak punch velocity, and impact velocity (p < 0.05), thus highlighting their greater power. CONCLUSIONS: In this cohort of 17 elite boxers, pronounced asymmetry was observed between lead- and rear-hand straight punches. Lead-hand punches were associated with shorter movement completion times, whereas rear-hand punches showed greater trunk rotational ROM along with higher peak force and velocity outputs. These complementary features appear to reflect a 'speed-power' technical pattern. We recommend that future longitudinal studies investigate unilateral and combined unilateral-bilateral training interventions in relation to the observed limb asymmetry.