Runners are susceptible to bone stress injuries (BSI), due in part to cumulative loading, which is affected by force magnitude and frequency. We identified biomechanical variables that may predict BSI incidence by following 30 collegiate distance runners over three years. Athletes were classified as either uninjured (n = 8 male, 16 female) or injured (n = 3 male, 3 female) if they sustained a BSI. We measured ground reaction forces while athletes ran on a force-instrumented treadmill, and analysed step frequency (f_step), contact length (L_c), and bodyweight-normalised stance average vertical ground reaction force (F_avg) alongside asymmetry (expressed as symmetry index, SI). A secondary analysis examined inter-limb biomechanical changes in six runners prior to sustaining a BSI. We found an interaction between injury status, sex, and speed on F_avg values (p = 0.026). Forty-seven weeks prior to injury, F_avg values were greater in the unaffected leg than the affected leg (p = 0.022). In addition, female injured runners exhibited 1.62 percentage points greater f_step SI than uninjured females at 4.9 m/s (p = 0.030). Future research that incorporates more frequent data collection is needed to integrate biomechanical variables and physiological risk factors for injury prediction and prevention among collegiate distance runners.

Keywords: Injury; running; speed; symmetry index.

跑步者容易遭受骨应力损伤（BSI），部分原因是累积负荷的影响，而累积负荷又受到力的大小和频率的影响。我们通过追踪30名大学生长跑运动员三年的情况，确定了可能预测BSI发生率的生物力学变量。如果运动员在研究期间受伤，则被分类为“受伤”组（男性3人，女性3人），否则为“未受伤”组（男性8人，女性16人）。我们在跑步机上测量了运动员的地面对抗力，并分析了步频（f_step）、接触长度（L_c）和体重校准的站立平均垂直地面对抗力（F_avg），以及不对称性（以对称指数，SI表示）。二次分析检查了六名运动员在受伤前下肢生物力学的变化。我们发现损伤状态、性别和速度之间对F_avg值存在相互作用（p=0.026）。在受伤前47周内，未受影响腿的F_avg值大于受影响腿的值（p=0.022）。此外，在每秒4.9米的速度下，受伤女性运动员的步频SI比未受伤女性高1.62个百分点（p=0.030）。为了在预测和预防大学长跑运动员的损伤中整合生物力学变量和生理风险因素，未来的研究需要更频繁的数据采集。

关键词：损伤；跑步；速度；对称指数。