Analysis of different stop-jumping strategies on the biomechanical changes in the lower limbs

The Stop-jumping task is one of the most important technical actions in basketball. A previous study showed 70% probability of non-contact ACL injuries during stop-jumping tasks. Therefore, the present study aimed to investigate the differences in lower extremity biomechanical changes between the rear foot as the initial contact area to stop the jump (SJR) and the fore foot, as the initial contact area to stop the jump (SJF) during the horizontal landing during a stop-jumping phase. 25 male amateur Ningbo University basketball athletes from China were recruited for this study. The participants were asked to jump vertically by using two different stop-jumping strategies. Kinematic and kinetics data were amassed during a stop-jumping task. Statistical Parametric Mapping (SPM) analysis was used to find the differences between SJR and SJF. Our results indicated that the change of different ankle range of motion caused significantly different values for the knee angle (p<0.001), velocity (p=0.003) (p=0.023) (p<0.001), moment (p=0.04) (p<0.001) (p=0.036) and power (p=0.015) (p<0.001) during the stop-jumping phase the horizontal landing phase. The same biomechanical parameters of the hip joint were also significantly different for the hip angle (p<0.001), moment (p=0.012) (p<0.001) (p<0.001) and power (p=0.01) (p<0.001) (p<0.001). These findings indicate that altering the primary contact at the ankle angle might effectively reduce the risk of a knee injury.