Key Laboratory of Exercise and Health Sciences of Ministry of Education,Shanghai University of Sport
目的：虽然跑步时跟腱的过劳损伤发生率很高,但是不同跑鞋对跟腱负荷特征的影响尚不清楚。本研究探究不同鞋条件(极简鞋和传统跑鞋)对跑步时跟腱负荷特征的影响。方法：实验招募16名健康男性后跟着地跑步爱好者,要求其以3.33米/秒(±5%)的速度在两种鞋条件下完成跑步实验。采用超声影像仪获取跟腱横截面积成像。采用运动捕捉系统和三维测力台获取踝关节矢状面运动学和地面反作用力数据,并计算踝关节和跟腱的力学参数。采用配对样本t检验比较两种鞋条件对各因变参数(踝关节角度、触地角度、跟腱力、应力、应变等)的影响。结果：与传统跑鞋相比,穿着极简鞋时的足触地角度显著降低39.9%(p < 0.001)。同时,踝关节力矩(p = 0.003)、跟腱力峰值(p = 0.003)、跟腱负载率峰值(p = 0.050)和平均负载率(p = 0.004)均显著增加,而达到跟腱力峰值的时间显著减小(p = 0.001)。此外,穿着极简鞋时的跟腱应力峰值(p = 0.005)、跟腱应变峰值(p = 0.005)及其应力率和应变率峰值(p = 0.014)也显著增加。结论：本研究发现,习惯穿着传统跑鞋并采用后跟着地的跑者在穿着极简鞋后显著增加了跟腱的负荷特征(如跟腱力、跟腱力冲量、跟腱应力),建议该类跑者循序渐进地过渡至极简鞋,以适应性地提高跟腱承受负荷的能力。
Purpose: Although the overuse injury rate of the Achilles tendon (AT) for running is high, the effect of shoe conditions on AT mechanical properties remains unclear. Hence, the purpose of this study is to determine the mechanical properties of AT during running under different shoe conditions (minimalist vs. conventional shoes). Methods: Sixteen healthy male rearfoot strike runners were recruited to complete over ground running trials at 3.33 m/s (±5%) under two shoe conditions. The cross-sectional area of the AT was obtained by ultrasound imaging. Sagittal plane ankle kinematics and ground reaction forces were recorded by motion capture system and a force platform simultaneously. Ankle mechanics and the mechanical properties of the AT were calculated. Result: Foot inclination angle was reduced by 39.9% with minimalist shoes (p＜0.001). Increases in ankle moment (p = 0.003), peak AT force (p = 0.003), peak AT loading rate (p = 0.050), and average loading rate (p = 0.004), and decrease in time to peak AT force with minimalist shoes (p = 0.001) were observed. Peak AT stress (p = 0.005), strain (p = 0.005), and corresponding peak rate (p = 0.014) also increased in minimalist shoes. Conclusion: Greater AT mechanical properties were observed in runners who habitually wear conventional shoes with rearfoot strike patterns when they wore minimalist shoes. Hence, we recommend a gradual transition to minimalist shoes for runners who habitually wear conventional shoes with rearfoot strike patterns to improve the ability to load.