Raw data of main figures used in this study.

This study investigated lower extremity biomechanics when running on different surfaces among runners with different footstrike patterns. Thirty rearfoot strikers (RFSs) and non-rearfoot strikers (nRFSs) ran at 3.3 m/s on a specially designed indoor track covered with three surfaces: artificial grass, synthetic rubber, and concrete. A motion capture system with ten cameras combined a force plate was used to collect marker trajectory and ground reaction force (GRF) during the running stance phase. A two-way analysis of variance with statistical parametric mapping was employed to evaluate differences in the biomechanics of the lower extremities between footstrike patterns and among running surfaces. The nRFSs exhibited significantly greater ankle inversion angles and increased inversion and internal rotation moments at midstance compared to the RFSs. Conversely, the RFSs demonstrated significantly greater knee abduction moments in late stance. Running on stiffer surfaces was associated with greater vertical GRF in late stance, as well as increased knee and hip extension moments during midstance. Furthermore, running on stiffer surfaces was associated with increased knee abduction moments, hip abduction moments, and hip external rotation moments during late stance. These findings suggested that nRFSs endure more ankle loads, while RFSs face increased knee loads. However, regardless of the footstrike pattern, runners may benefit from selecting softer surfaces to reduce the risk of injury.

本研究针对不同足触地模式的跑步者在不同路面跑步时的下肢生物力学特征展开探究。招募30名后足触地者（rearfoot strikers, RFSs）与非后足触地者（non-rearfoot strikers, nRFSs），令其以3.3 m/s的速度在铺设三种路面的特制室内跑道上跑步：人造草坪、合成橡胶与混凝土。采用搭载10台摄像头的运动捕捉系统结合测力台，采集跑步支撑阶段的标记点轨迹与地面反作用力（ground reaction force, GRF）数据。采用结合统计参数映射的双因素方差分析，对比不同足触地模式间以及不同跑步路面下的下肢生物力学差异。相较于RFSs，nRFSs在支撑中期的踝关节内翻角度显著更大，内翻力矩与内旋力矩亦显著升高。反之，RFSs在支撑后期的膝关节外展力矩显著更高。在刚度更高的路面跑步时，支撑后期的垂直地面反作用力更大，且支撑中期的膝关节与髋关节伸力矩均有所升高。此外，在刚度更高的路面跑步时，支撑后期的膝关节外展力矩、髋关节外展力矩与髋关节外旋力矩均有所增加。上述结果表明，nRFSs承受更大的踝关节负荷，而RFSs则面临更高的膝关节负荷。不过无论采用何种足触地模式，跑步者选择较软的路面均可降低运动损伤风险，从而获益。