Department of Rehabilitation for the Movement Functions, Research Institute, National Rehabilitation Center for Persons with Disabilities, 4-1 Namiki, Tokorozawa, Saitama, Japan.
Eur J Appl Physiol. 2012 Oct;112(10):3641-8. doi: 10.1007/s00421-012-2351-7. Epub 2012 Feb 16.
This study was undertaken to elucidate the impact of long-term physical training on the modulation of stretch reflex excitability. To this end, electromyographic activities of the soleus muscle in response to quick toe-up rotation were compared between highly trained endurance runners (n = 8) and non-trained control subjects (n = 9). We specifically focused on the stretch reflex modulation under different voluntary activation levels, from rest to pre-activated conditions (5, 10, 20, and 30% of the maximal). While the two groups showed similar modulation patterns of the stretch reflex responses, the extent of reflex modulation in accordance with the muscle pre-activation level was larger in the trained group. The present results therefore suggest a different modulation pattern of the stretch reflex responses with changing activation level between individuals with different physical background, and the enhancement of the responses in the trained individuals may particularly be advantageous in exerting high level muscle contraction.
本研究旨在阐明长期体育锻炼对牵张反射兴奋性调节的影响。为此，比较了经过长期耐力训练的跑步运动员（n = 8）和未经训练的对照组受试者（n = 9）对快速脚趾上翘旋转的比目鱼肌肌电图活动。我们特别关注不同自愿激活水平下的牵张反射调节，从休息到预激活状态（5%、10%、20%和 30%最大）。虽然两组的牵张反射反应的调节模式相似，但在训练组中，根据肌肉预激活水平的反射调节程度更大。因此，本研究结果表明，不同身体背景的个体之间的牵张反射反应的调节模式不同，并且在训练个体中，反应的增强可能特别有利于发挥高水平的肌肉收缩。
