跑步疲劳后对下肢生物力学的影响--以女性新手跑者为例

The Effect of Running Fatigue on Lower Limb Biomechahics:A Case Study of Female Novice Runners

目的:对比新手女性跑者跑步疲劳前后的下肢生物力学差异,为女性新手跑者科学化训练和运动损伤提供理论参考。方法:15名女性新手受试者,采用Vicon三维运动捕捉系统和Kislter三维测力台采集受试者跑步疲劳前后的下肢运动学和下肢动力学参数。跑步疲劳方式是受试者在跑台13.3km/h,然后逐渐递增跑步机速度。疲劳状态需满足以下条件:①受试者将无法再进行跑步;②疲劳量表Bro分数大于或等于17;③达到受试者90%的最大心率,根据年龄和公式计算受试者的最大心率(HRmax 220-age)。数据采用SPSS配对样本T检验和Statistical Parametric Mapping(SPM)1d(一维统计参数映射)SPM1d对关节角度、关节力矩和关节功率数据进行检验。结果:①跑步疲劳后髋关节最大伸展角度、髋关节屈伸活动范围和踝关节最大跖屈角速度显著增大(P<0.05);②踝关节最大背屈力矩明显减小,但是膝关节最大伸展力矩显著增大(P<0.05);③跑步疲劳后,踝关节最大背屈功率、踝关节最大跖屈功率、髋关节最大屈曲功率均显著减小(P<0.05),膝关节最大屈曲功率显著增大(P<0.05)。研究结论:①跑步疲劳后,下肢生物力学参数发生显著变化,特别是增大的髋关节最大伸展角度和髋关节最大屈伸活动范围会加大髋关节的应力从而导致髋关节损伤风险增大;②跑步疲劳后下肢功率从远端踝关节向近端膝关节增加,提示跑步疲劳后应注意膝关节损伤。因此,女性新手跑者应科学化训练合理安排跑步训练量并加大下肢力量练习,降低跑步疲劳造成的运动损伤风险。

Objective:This study aimed to compare the biomechanical differences in the lower limbs of novice female runners in the pre and post-fatigue running conditions.To decrease running injuries and provide a theoretical reference for scientific training and sports injury prevention.Methods:Fifteen novice female runners participated in this study,using the Vicon three-dimensional motion capture system and Kistler three-dimensional force plate to collect lower limb kinematics and kinematic data pre and post-running fatigue.Running fatigue was induced by increasing treadmill speed starting at 13.3 km/h until the subjects could no longer continue running.The criteria for fatigue included:①the inability to continue running;②a Borg scale of perceived exertion score of 17 or above;③reaching 90%of maximum heart rate(HRmax 220-age).Data were analyzed using paired sample T-tests and Statistical Parametric Mapping(SPM)1D from SPSS.Results:①Compared to pre-fatigue running,the hip peak extension angle,the hip joint's range motion,and ankle peak plantar flexion angular velocity significantly increased in the post-fatigue running(P<0.05);②ankle peak dorsiflexion moment was significantly decreased,but the knee peak extension moment was significantly increased(P<0.05);③ankle peak dorsiflexion power,ankle peak plantar flexion power,hip peak flexion power were significantly increased in the post-fatigue running conditions.Conclusions:The lower limb biomechanical variables were significantly changed after the fatigue running,especially in the large hip peak extension angles and range motion of the hip joint,which could lead to increasedhip joint force and increased risk of hip joint injuries.The redistribution of power from the distal ankle to the proximal knee post-fatigue suggests a heightened risk of knee injuries.Therefore,novice female runners should undertake scientifically based training,properly schedule running volumes,and enhance lower limb strength exercises to reduce the risk of injuries caused by running fatigue.