Influences of joint dynamics on take-off velocity in elite male 110-m hurdlers

Objective To study the relationship between lower limb joint moments, joint stiffness, and take-off velocity in high-level hurdlers. Methods This study employed a Qualisys three-dimensional infrared motion-capture system synchronized with a force plate. Based on inverse dynamics principles, kinematic and kinetic data were collected during the clearance phase over the fourth hurdle in 16 elite male 110-m hurdlers. Results During the landing phase, Group B had significantly higher peak joint moments at the hip, knee, and ankle compared to Group A ( P < 0.01). During the propulsive phase, Group B had significantly higher peak joint moments at the hip, knee, and ankle compared to Group A( P < 0.01). Group B had significantly higher joint stiffness at the hip, knee, and ankle compared to Group A ( P < 0.01). During the landing phase, the relative peak joint moments at the hip, knee, and ankle were positively correlated with landing velocity, with correlation coefficients ( r ) ranging from 0.51 to 0.61. During the propulsive phase, the relative peak moments at these joints were highly positively correlated with take-off velocity, with r values between 0.82 and 0.89. Hip, knee, and ankle joint stiffness was highly positively correlated with clearance velocity ( r : 0.80–0.90) but highly negatively correlated with the rate of change in velocity ( r : −0.88 to −0.95). Conclusions During the take-off phase, Group B exhibited greater relative peak joint moments and joint stiffness at the hip, knee, and ankle compared to Group A. These measures were strongly correlated with clearance velocity, indicating that increasing joint moments and stiffness contributes to faster hurdle clearance. Among the lower-limb joints, hip and ankle performance had the most significant influence on clearance mechanics. Additionally, the fitted functional equations enable prediction of clearance velocity from joint moment data. Therefore, incorporating stretch-shortening cycle exercises in training to enhance lower-limb strength, increase joint moments, and improve joint stiffness should effectively enhance performance and competitive outcomes.