Volleyball players often land on a single leg following a spike shot because of a shift in the center of gravity. This landing is one of the high-risk actions for non-contact ACL injury. The purpose of this study was to compare and analyze the discrete and temporal kinematics and kinetics associated with functional valgus collapse during volleyball in player landing phases during a single-leg landing and double-leg landing following a spike shot. Kinematics and kinetics data were collected (captured by a Vicon motion system and AMTI force plate, processed by Visual-3D software) during the single-leg and double-leg landing phases in 13 semi-professional male volleyball players. The landing phase was defined as initial ground contact (0% landing phase) to maximum knee flexion (100% landing phase). Statistical Parametric Mapping (SPM) analysis revealed that single-leg landing depicted a significantly greater knee abduction angle and hip adduction moment than double-leg landing during the 0%–68% landing phase (single-leg: 7°–16°, double-leg: 0°–9°, p < 0.001) and 18%–22% (single-leg: 0.62–0.91 Nm/kg, double-leg: 0.08–0.19 Nm/kg, p = 0.0063) landing phase, respectively. The traditional discrete analysis revealed that single-leg landing depicted a significantly greater peak knee internal rotation moment (single-leg: 1.46 ± 0.38 Nm/kg, double-leg: 0.79 ± 0.19 Nm/kg, p = 0.006) and peak hip internal rotation moment (single-leg: −2.20 ± 0.54 Nm/kg, double-leg: −0.88 ± 0.30 Nm/kg, p = 0.011) than double-leg landing. Most differences were within a time frame during the landing phase of 30–50 ms in which non-contact ACL injuries are considered to happen. These recorded time frames are consistent with biomechanical measures that are deemed dangerous. To reduce lower limb injury, a volleyball player should consciously swing the arms to influence the body to maintain a better-balanced state. Adjusting the landing mode of the lower limbs can achieve a good cushioning effect during landing following a spike shot.

排球运动员由于重心移动而经常在挥杆后落在一条腿上。降落是非接触式ACL伤害的高风险措施之一。本研究的目的是比较和分析与单发着陆和双发着陆之后的排球阶段排球过程中与功能性外翻倒塌相关的离散和时间运动学和动力学。在13名半职业男排运动员的单腿和双腿着陆阶段，收集了运动学和动力学数据（通过Vicon运动系统和AMTI推力板捕获，通过Visual-3D软件处理）。着陆阶段定义为初始地面接触（0％着陆阶段）至最大膝盖屈曲（100％着陆阶段）。p  <0.001）和18％–22％（单腿：0.62–0.91 Nm / kg，双腿：0.08–0.19 Nm / kg，p  = 0.0063）着陆阶段。传统的离散分析显示，单腿着陆表现出明显更大的膝盖内部旋转力矩峰值（单腿：1.46±0.38 Nm / kg，双腿：0.79±0.19 Nm / kg，p  = 0.006）和髋骨内部峰值旋转力矩（单腿：−2.20±0.54 Nm / kg，双腿：−0.88±0.30 Nm / kg，p = 0.011）。大多数差异是在着陆阶段30–50 ms的时间范围内，在该时间段内，非接触式ACL受伤被认为发生了。这些记录的时间范围与被认为是危险的生物力学措施一致。为减少下肢受伤，排球运动员应自觉地挥动手臂以影响身体，以保持更好的平衡状态。调整下肢的着陆方式可以在峰值射击后的着陆过程中获得良好的缓冲效果。