Key Laboratory of Exercise and Health Sciences of Ministry of Education,Shanghai University of Sport
National Natural Science Foundation funded projects (11772201, 81572213); National Key Research and Development Program "Science and Technology Winter Olympics" key projects (2018YFF0300500); Shanghai Science and Technology Commission research project (17080503300); Shanghai Talent Development Fund funded projects (2018107)
目的 建立12周跑姿再训练（gait retraining，GR）的干预模式（即通过一定的姿态目标改变跑者原有跑姿），确定GR前后跑步时垂直地面反作用力（vGRF）、髋/膝/踝运动学、动力学和下肢刚度特征的变化，探究跑姿转换对冲击力和下肢生物力学的影响。方法 采用Vicon 运动捕捉系统和Kistler三维测力台同步采集30名跑步爱好者（GR组15人，对照组15人）跑姿再训练前后穿着极简鞋以3.33±5％m/s的速度通过测力台的地面反作用力以及标记点轨迹。结果 共17名受试者（GR组9人，对照组8人）完成训练；训练后：1）两组在最大负载率都显著下降，GR组相比对照组最大负载率更低；2）GR组足部触地角度显著减小，两组跖屈角度和髋关节蹬伸角速度都显著增加；3）GR组踝关节力矩增加；GR组（+17.2%）与对照组（+7.1%）的下肢刚度均显著增加。结论 成功建立12周跑姿再训练（GR）的运动干预模型（前掌着地转化率为78%）。具体表现为：GR训练能有效避免冲击力峰值、降低最大负载率、提高下肢刚度，进而在减小甚至避免由冲击力引起的跑步损伤风险的同时，为提高跑步经济性提供了可能。
Purpose The intervention mode of 12-week gait retraining (with the specific aim of changing the habitual running gait) was established to determine the changes of vertical ground reaction force (vGRF), hip/knee/ankle kinematics, dynamics and stiffness characteristics of lower limbs before and after GR running, and to explore the influence of running posture transformation on impact force and lower limb biomechanics. Methods Vicon motion capture system and Kistler 3d force measurement platform were used to collect the ground reaction force and mark point track of 30 runners (15 in the experimental group and 15 in the control group) before and after retraining with minimalist shoes at a speed of 3.33±5％m/s. Results a total of 17 subjects (9 in the experimental group and 8 in the control group) completed the training. After training: 1) the maximum loading rate of both groups decreased significantly, and the maximum loading rate of the experimental group was lower than the control group. 2) the foot strike angle of the experimental group decreased significantly after training, and the plantarflexion Angle and hip joint angular extension velocity increased in both groups. 3) the moment of ankle joint increased in the experimental group, and the stiffness of lower limbs was significantly improved in both groups. Conclusion A 12-week gait retraining (GR) exercise intervention model was established to convert runners who used to rearfoot strike to forefoot strike (conversion rate 78%). Specific on: GR training can effectively avoid the peak of impact force, reduce the maximum loading rate, increase the lower limb stiffness, and thus reduce or even avoid the risk of running injury caused by impact force and may provide a possibility for the improvement of running economy and corresponding energy utilization rate.