BEHAVIOR OF TRICEPS SURAE MUSCLE-TENDON COMPLEX IN DIFFERENT JUMP CONDITIONS
BEHAVIOR OF TRICEPS SURAE MUSCLE-TENDON COMPLEX IN DIFFERENT JUMP CONDITIONS
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DOI：
10.1007/bf00636213
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发表时间：
1992-04-01
影响因子：
3
通讯作者：
SCHWEIZER, L
中科院分区：
文献类型：
--
作者：
GOLLHOFER, A;STROJNIK, V;SCHWEIZER, L
研究了在各种拉伸负载条件下，小腿三头肌和跟腱的人体肌肉肌腱复合体（MTC）的力-长度关系。六名男性受试者以最大努力进行了各种垂直跳跃：从 24 厘米、40 厘米和 56 厘米的高度进行深蹲跳 (SJ)、反向运动跳 (CMJ) 和跳下跳 (DJ)。根据地面反作用力分量的信号和从高速胶片记录中获得的运动学数据计算力-长度关系。还记录了比目鱼肌、腓肠肌和胫骨前肌的表面肌电图（EMG）。力-长度图显示出个体对所施加的拉伸载荷的高敏感性。在拉伸负载要求相对较低的情况下，可观察到逆时针方向，这表明在偏心或延长阶段吸收的能量低于在向心或缩短阶段传递的能量。在高负载条件下，这种关系相反，表明负能量平衡。 SJ 和 CMJ 的肌电图长度图包括肌肉的初始等长负荷，随后是肌电图振幅仅略有降低的缩短阶段。然而，在 DJ 中，图表显示 MTC 最初延长，激活幅度相当恒定。 40 毫秒后，肌肉进行等长负荷，持续约 80 毫秒，随后是缩短阶段。结论是，节段性牵张反射激活代表了等长加载阶段的主要激活过程，以满足 MTC 足够的刚度特性。
The force-length relationship of the human muscle-tendon complex (MTC) of the triceps surae and the achilles tendon was investigated in various stretch load conditions. Six male subjects performed various vertical jumps with maximal effort: squat jumps (SJ), counter movement jumps (CMJ) and drop jumps (DJ) from a height of 24 cm, 40 cm and 56 cm. The force-length relationship was calculated from the signals of the components of the ground reaction forces and the kinematic data obtained from the high-speed film records. Surface electromyograms (EMG) of the soleus, gastrocnemius and tibialis anterior muscles were also recorded. The force-length diagrams showed individually high sensitivity to the imposed stretch load. In conditions with relatively low stretch load requirements there was a counter-clockwise direction observable, indicating that the energy absorbed during the eccentric, or lengthening phase was lower than the energy delivered during the concentric, or shortening phase. In high load conditions this relationship was reversed indicating a negative energy balance. The EMG-length diagrams of SJ and CMJ consisted of an initial isometric loading of the muscle, followed by a shortening phase with only slightly reduced EMG amplitudes. In DJ, however, the diagrams showed an initial lengthening of the MTC with fairly constant activation amplitudes. After 40 ms an isometric loading of the muscle, lasting for approximately 80 ms, was followed by a shortening phase. It was concluded that segmental stretch reflex activation represented the predominant activation process during the isometric loading phase, to meet the adequate stiffness properties of the MTC.