A STUDY ON EFFECTS OF PROGRAMED EXERCISE TRAINING ON BALANCING ABILITY AGAINST ABRUPT DECELERATION IN THE ELDERLY

本研究的目的是探讨多维运动训练对老年人平衡能力对抗突然减速的影响。20名社区居住的健康老年人（≧65岁）在过去6个月内没有跌倒史。将患者分为运动组（n=10）和对照组（n=10）。为期12个月的运动训练计划旨在增加力量，下肢灵活性，动态平衡和ADL。对照组不进行干预。测量平台减速后体位摇摆过程中足中心压力（CFP）的变化，评估响应时间和CFP位移。测量突然加速时胫骨前肌和腓肠肌内侧肌的肌电图，计算下肢肌群中拮抗肌共收缩的相对水平。此外，还测量了运动和感觉能力。结果表明：1)与训练前相比，训练组在训练后突然减速后的反应时间和CFP位移均有显著改善（p <0.05）。2)训练组CCI在训练后显著低于训练前（p <0.05）。3)训练组在跖屈肌、背屈肌、膝伸肌力量、踝关节和髋关节柔韧性、选择反应时间、单腿平衡时间、坐立时间、尽可能快的行走速度等方面均有显著改善（p <0.05）。这些结果表明，12个月的运动训练可以提高对突然减速的平衡能力，从而降低跌倒的风险。这可能是因为神经肌肉功能的改善。

The purpose of this study was to examine the effects of a multidimensional exercise training on balancing ability against abrupt deceleration in the elderly. Twenty community-dwelling healthy elderly (≧65 years of age) with no history of one or less falls in the previous 6 month participated. They were classified into exercise group (n=10) and control group (n=10). The 12-month exercise training program was designated to increase strength, flexibility of the lower extremities, dynamic balance and ADL. The control group received no intervention. Changes in the center of foot pressure (CFP) were measured during postural sway following platform deceleration, and the response time and CFP displacement were evaluated. The EMG onset in the tibialis anterior muscle and medial gastrocnemius muscle during abrupt acceleration was measured, and the relative level of co-contraction of antagonistic muscles (CCI) in the lower extremity muscle group was calculated. In addition, motor and sensory abilities were measured.Results were as follows :1) Significant improvement were observed in training group for the response time and CFP displacement immediately after abrupt deceleration in post-training vs pre-training (p <0.05).2) CCI in training group was significantly lower in post-training than in pre-training (p <0.05).3) Significant improvement were observed in training group for the strength of planterflexor and dorsiflexor muscles, and knee extensor muscle, flexibilities of ankle and hip joints, choice reaction time, one leg balancing time, time to sit-to-stand, and speed of walking as fast as possible (p <0.05).These results suggest that this exercise training for 12-month can improve the balancing ability against abrupt deceleration, thereby reducing risk for falls. This may be because improvement of neuro-muscular function.