Neural Compensation Within the Human Triceps Surae During Prolonged Walking
Neural Compensation Within the Human Triceps Surae During Prolonged Walking
复制标题
DOI：
10.1152/jn.00967.2010
复制
发表时间：
2011-02-01
影响因子：
2.5
通讯作者：
Avela, Janne
中科院分区：
文献类型：
--
作者：
Cronin, Neil J.;Peltonen, Jussi;Avela, Janne
张建军，张建军，张建军，等。长时间步行时肱三头肌的神经代偿。中国生物医学工程学报（英文版），2009,31(5):548-553。首次发表于2010年12月15日；doi: 10.1152 / jn.00967.2010。在人类行走过程中，肌肉激活策略在短时间内连续行走的过程中大致是恒定的，但它们是否在较长时间内保持不变尚不清楚。长时间步行可能会增加肌腱组织（TT）的顺应性，这可能会影响神经激活，但尚未对单个肌肉的神经反应进行研究。本研究调查了在长时间步行过程中，肌肉活动在个体三头肌表面肌肉中向上或向下调节的假设。13名健康受试者在跑步机上以4.5 km/h的速度步行60分钟，每5分钟记录一次肱三头肌表面肌活动、最大肌肉复合动作电位和运动学，并在实验开始和结束时使用超声估计肌束长度。步行1 h后，比目鱼肌活动增加9.3 +/- 0.2% (P < 0.05)，腓肠肌内侧活动减少9.3 +/- 0.3% （P < 0.01）。腓肠肌与地面接触时肌束长度缩短了4.45±0.99% (P < 0.001)，而比目鱼肌束长度没有变化（P = 0.988）。在整个站立期，腓肠肌内侧束的延长幅度下降了44 +/- 13% (P < 0.001)，而比目鱼肌束的延长幅度没有变化（P = 0.650）。数据表明，三头肌表面肌之间存在一种代偿性神经策略，肌肉激活的变化通常反映在肌束长度的变化上。这些发现也支持了长时间步行后TT顺应性的肌肉特异性变化的概念，并强调了尽管单个肌肉的神经力学变化，但中枢神经系统保持相对恒定运动模式的能力。
Cronin NJ, Peltonen J, Sinkjaer T, Avela J. Neural compensation within the human triceps surae during prolonged walking. J Neurophysiol 105: 548-553, 2011. First published December 15, 2010; doi:10.1152/jn.00967.2010. During human walking, muscle activation strategies are approximately constant across consecutive steps over a short time, but it is unknown whether they are maintained over a longer duration. Prolonged walking may increase tendinous tissue (TT) compliance, which can influence neural activation, but the neural responses of individual muscles have not been investigated. This study investigated the hypothesis that muscle activity is up-or down-regulated in individual triceps surae muscles during prolonged walking. Thirteen healthy subjects walked on a treadmill for 60 min at 4.5 km/h, while triceps surae muscle activity, maximal muscle compound action potentials, and kinematics were recorded every 5 min, and fascicle lengths were estimated at the beginning and end of the protocol using ultrasound. After 1 h of walking, soleus activity increased by 9.3 +/- 0.2% (P < 0.05) and medial gastrocnemius activity decreased by 9.3 +/- 0.3% (P < 0.01). Gastrocnemius fascicle length at ground contact shortened by 4.45 +/- 0.99% (P < 0.001), whereas soleus fascicle length was unchanged (P = 0.988). Throughout the stance phase, medial gastrocnemius fascicle lengthening decreased by 44 +/- 13% (P < 0.001), whereas soleus fascicle lengthening amplitude was unchanged (P = 0.650). The data suggest that a compensatory neural strategy exists between triceps surae muscles and that changes in muscle activation are generally mirrored by changes in muscle fascicle length. These findings also support the notion of muscle-specific changes in TT compliance after prolonged walking and highlight the ability of the CNS to maintain relatively constant movement patterns in spite of neuromechanical changes in individual muscles.