跑鞋纵向抗弯刚度调整对青少年下肢生物力学影响的研究

Effects of running shoes’increased longitudinal bending stiffness on lower limb biomechanics of adolescent runners

探讨青少年跑者在不同纵向抗弯刚度(longitudinal bending stiffness,LBS)跑鞋条件下进行跑步运动时的下肢生物力学参数变化。选取10名有一定训练基础的约13周岁青少年跑者,年龄(13.5±0.6)岁;身高(166.3±1.9)cm;体质量(50.8±3.1)kg;足长(25.4±0.2)cm,分别选用3种LBS不同的跑鞋(低刚度鞋:5.0 N·m;中刚度鞋:6.3 N·m;高刚度鞋:8.6 N·m)进行跑步运动生物力学综合测试,通过VICON三维运动捕捉系统和AMTI三维测力台同步采集受试者下肢反光标记点轨迹和地面反作用力,分析比较不同LBS跑步支撑期的下肢关节角度、峰值力矩、关节功率和做功变化。在3种不同LBS条件下,中刚度鞋和高刚度鞋的髋关节屈伸活动度显著小于低刚度鞋;高刚度鞋的跖趾关节屈伸活动度显著小于低刚度鞋与中刚度鞋;矢状面上,中刚度鞋和高刚度鞋的髋关节峰值力矩显著小于低刚度鞋;低刚度鞋与中刚度鞋的踝关节峰值力矩显著小于高刚度鞋;中刚度鞋和高刚度鞋的跖趾关节峰值力矩显著小于低刚度鞋。中刚度鞋和高刚度鞋髋关节做正功和负功显著小于低刚度鞋;中刚度鞋和高刚度鞋膝关节做正功显著小于低刚度鞋;低刚度鞋膝关节做负功显著大于中刚度鞋;中刚度鞋和高刚度鞋踝关节做正功和负功显著大于低刚度鞋。随着跑鞋LBS增加,青少年跑者伸髋角度、峰值力矩、关节做功减小,踝关节跖屈角度减小、关节做功增大,跖趾关节屈曲活动度和峰值力矩降低。恒定跑速下,随着鞋具LBS调整,下肢做功在不同关节间出现转移与重新分布。青少年跑者不同LBS的下肢运动生物力学参数可能为跑鞋LBS设计与优化提供科学参考。

To investigate the biomechanical parameters of the lower limbs of adolescent runners under different longitudinal bending stiffness(LBS)running shoe conditions.Ten adolescent runners[age(13.5±0.6)years;height(166.3±1.9)cm;body mass(50.8±3.1)kg;foot length(25.4±0.2)cm]with some training experience were selected to run in three different longitudinal bending stiffness shoes(low-stiffness shoe:5.0 N·m;medium-stiffness shoe:6.3 N·m;and high-stiffness shoe:8.6 N·m).The VICON 3 D motion capture system and AMTI 3 D force measuring platform were used to collect the trajectories of the lower limb marker points and ground reaction forces simultaneously and to analyze and compare the changes in joint angles,peak moments,joint power,and work done at different longitudinal flexural stiffness.Under the three different bending stiffness conditions,the hip joint mobility in medium-and high-stiffness shoes was significantly less than that in low-stiffness ones;the metatarsophalangeal joint mobility in high-stiffness shoes was significantly less than that in low-and medium-stiffness ones.On the sagittal plane,the peak hip joint moment in medium-and high-stiffness shoes was significantly less than that in low-stiffness ones;peak ankle joint moments were significantly smaller in low-and medium-stiffness shoes than in high-stiffness ones;peak metatarsophalangeal joint moments were significantly smaller in medium-and high-stiffness shoes than in low-stiffness ones;The positive and negative hip joint work of medium-and high-stiffness shoes was significantly less than the low-stiffness ones.The negative knee joint work of low-stiffness shoes was significantly higher than that of medium-stiffness ones.The positive and negative ankle joint work in medium-and high-stiffness shoes was significantly higher than that of low-stiffness ones.As the LBS of running shoe increases,hip extension angle,peak torque and joint work decrease,ankle plantarflexion angle decreases,joint work increases,and metatarsophalangeal joint flexion range of motion and peak torque decreases.At a constant running speed,with the adjustment of the shoe LBS,the work of the lower limbs is transferred and redistributed among different joints.The biomechanical parameters of lower extremity movement of young runners with different LBS may provide scientific reference for the design and optimization of running shoe LBS.