Higashihara Ayako, Nagano Yasuharu, Takahashi Kazumasa, Fukubayashi Toru
a The Japan Society for the Promotion of Science , Tokyo , Japan.
J Sports Sci. 2015;33(13):1366-75. doi: 10.1080/02640414.2014.990483. Epub 2014 Dec 16.
This study aimed to investigate the effects of forward trunk lean on hamstring muscle kinematics during sprinting. Eight male sprinters performed maximal-effort sprints in two trunk positions: forward lean and upright. A three-dimensional musculoskeletal model was used to compute the musculotendon lengths and velocity of the biceps femoris long head, semitendinosus, and semimembranosus muscles during the sprinting gait cycle. The musculotendon lengths of all the three hamstring muscles at foot strike and toe-off were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. In addition, a positive peak musculotendon lengthening velocity was observed in the biceps femoris long head and semimembranosus muscles during the late stance phase, and musculotendon lengths at that instant were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. The present study provides significant evidence that a potential for hamstring muscle strain injury involving forward trunk lean sprinting would exist during the stance phase. The results also indicate that the biceps femoris long head and semimembranosus muscles are stretched during forward trunk lean sprinting while contracting eccentrically in the late stance phase; thus, the elongation load on these muscles could be increased.
本研究旨在探讨前倾躯干对短跑过程中腘绳肌运动学的影响。八名男性短跑运动员在两种躯干姿势下进行全力冲刺：前倾和直立。使用三维肌肉骨骼模型计算短跑步态周期中股二头肌长头、半腱肌和半膜肌的肌腱长度和速度。与直立躯干冲刺相比，前倾躯干冲刺时，在脚着地和脚趾离地时，所有三块腘绳肌的肌腱长度均显著更长。此外，在站立后期，股二头肌长头和半膜肌观察到正的峰值肌腱延长速度，且此时前倾躯干冲刺时的肌腱长度显著长于直立躯干冲刺时。本研究提供了重要证据，表明在站立阶段，前倾躯干冲刺存在腘绳肌拉伤的潜在风险。结果还表明，前倾躯干冲刺时，股二头肌长头和半膜肌在站立后期离心收缩时被拉长；因此，这些肌肉上的伸长负荷可能会增加。
