太极拳上步弓步动作足前进角对膝关节载荷的影响及肌肉协调收缩策略

目的考察太极拳运动姿势对膝关节载荷的影响及肌肉协调收缩策略。方法募集20名具有3年以上健康太极拳习练者,借助红外高速运动捕捉系统和三维测力台,采集太极拳上步弓步动作支撑腿内收角、胫骨角、关节力、关节力矩等参数,通过仿真方法获取股四头肌和腓肠肌肌肉力。比较惯用步、外展步和内收步肌肉力表现、募集模式和激活方式特征。结果外展步胫骨角和内收力增大,而内收步不变;外展步股内肌、半膜半腱肌及外侧腓肠肌力增大;内收步股外肌和内侧腓肠肌力增强,腓肠肌比股四头肌被优先激活,肌群募集方式发生改变。结论太极拳运动姿势改变肌肉力募集方式,影响膝关节功能,规范动作可作为骨性关节炎运动疗法借鉴,具有临床应用意义。

Influences of Foot Progression Angle during the Tai Chi Step Lunge Movement on Knee Joint Load and Strategy of Coordinated Muscle Contraction

Objective To investigate the influence of Tai Chi posture on knee joint load and the strategy of coordinated muscle contraction. Methods Twenty Tai Chi practitioners with more than 3 years of Tai Chi practice was recruited. By using high-speed motion capture system andthree-dimensional force plate, the adduction angle, tibial angle, joint force, joint torque of the supporting leg during the Tai Chi step lunge movement were collected, and the quadriceps and gastrocnemius muscle strength were obtained through simulation method. The muscle strength performance, recruitment mode and activation method of baseline step, toe-out step and toe-in step were compared. ResultsThe tibial angle and adduction force increased in the toe-out step but those parameters in the toe-in step remained unchanged; the strength of the medial femoris, semimembranosus, semitendinosus and lateral gastrocnemius muscle increased in the toe-out step; the external femoral muscle and medial gastrocnemius muscle increased in the toe-in step. The gastrocnemius muscle was preferentially activated than the quadriceps muscle, and the way of muscle recruitment changed. Conclusions Tai Chi posture will change the way of muscle force recruitment and affect the knee joint function. Standardized movements can be used as the reference for osteoarthritis exercise therapy and have some significance in clinical application.