Age and walking speed effects on muscle recruitment in gait termination
Age and walking speed effects on muscle recruitment in gait termination
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DOI：
10.1016/j.gaitpost.2004.03.002
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发表时间：
2005-04-01
期刊：
影响因子：
2.4
通讯作者：
Sparrow, WA
中科院分区：
文献类型：
--
作者：
Tirosh, O;Sparrow, WA
在以正常步行速度终止步态时，老年人比年轻人更频繁地采用两步反应，增加了他们的停止距离和停止时间。这项研究调查了衰老对以三种步行速度停止时下肢肌肉募集模式的影响。 12 名年轻男性（26 +/- 3.7 岁，范围 19-30）和 12 名性别匹配的老年参与者（72 +/- 4.3 岁，范围 65-82）终止以正常、中等和最大速度行走。在 30% 的试验中，左脚跟或右脚跟接触后 10 毫秒会出现视觉停止刺激，而没有任何刺激（捕捉）。记录胫骨前肌 (TA)、比目鱼肌 (SOL)、股二头肌 (1317)、股外侧肌 (VL) 和臀中肌 (GM) 的肌电图 (EMG) 活动。老年男性（46% 的试验）比年轻男性（20%）更频繁地采取两步停止。站立腿肌肉的反应速度明显快于摆动腿，并且随着速度的增加，有助于停止的摆动腿肌肉越来越少。老年男性对站立腿的反应较慢，在刺激后 215 毫秒，而年轻群体为 176 毫秒。他们还招募了更少的摆动腿肌肉，比目鱼肌和臀中肌的激活频率也更低。未能激活肌肉将提供较小的伸肌扭矩来维持前支撑基部之前的重心。这将减少与水平速度相反的总力，以使身体静止，从而鼓励在停止之前再迈出一步。 (c) 2004 Elsevier B.V. 保留所有权利。
During gait termination at normal walking speed, older adults more frequently employ two-step responses, increasing their stopping distance and stopping time more than younger controls. This study investigated ageing effects on lower limb muscle recruitment patterns during stopping at three walking speeds. Twelve young male (26 +/- 3.7 years, range 19-30) and 12 gender-matched older participants (72 +/- 4.3 years, range 65-82) terminated walking at normal, medium and maximum speed. A visual stopping stimulus was presented 10 ms following either left or right heel-contact with no stimulus (catch) on 30% of trials. Electromyographic (EMG) activity was recorded from the tibialis anterior (TA), soleus (SOL), biceps femoris (1317), vastus lateralis (VL) and gluteus medius (GM). Older males more frequently (46% of trials) took two-steps to stop than young males (20%). The stance leg muscles responded significantly faster than the swing leg, and with increased speed, fewer swing limb muscles contributed to stopping. Older males were slower to respond with the stance leg, at 215 ms following the stimulus compared with 176 ms for the younger group. They also recruited fewer swing leg muscles with less frequent activation of the soleus and gluteus medius. Failure to activate muscles would provide less extensor torque to maintain the centre of gravity anterior to the forward base of support. This would decrease the total force opposing horizontal velocity in order to bring the body to rest and, as a consequence, encourage an additional step prior to stopping. (c) 2004 Elsevier B.V. All rights reserved.