Department of Human Movement and Sport Sciences, University of Rome Foro Italico, Piazza Lauro De Bosis 6, 00135 Rome, Italy.
Muscle Nerve. 2012 Sep;46(3):434-9. doi: 10.1002/mus.23366.
The effect of recovery time on neuromuscular function after a fatiguing task was compared in both the upper and lower limbs between patients with Charcot-Marie-Tooth type 1A (CMT1A) and healthy individuals.
Torque of elbow flexors and knee extensors and surface electromyography (sEMG) data of biceps brachii and vastus lateralis were recorded from 8 CMT1A patients and 8 matched, healthy individuals during maximal voluntary contraction (MVC) before (pre-fatigue MVC), 10 s after (10-s post-fatigue MVC), and 10 min after (10-min post-fatigue MVC) a fatiguing task at 80% MVC until exhaustion.
Only in the lower limb, torque and root mean square of sEMG (RMS) during pre-fatigue MVC were lower (P < 0.05) in patients (91.93 ± 45.95 Nm, 0.11 ± 0.07 mV) than in controls (161.06 ± 75.5 Nm, 0.24 ± 0.16 mV). In the 10-min post-fatigue MVC, muscle-fiber conduction velocity (MFCV) and RMS, expressed as a percentage of pre-fatigue MVC, were lower (P < 0.05) in patients (MFCV 90.3 ± 6.91%, RMS 84.50 ± 9.89%) than in controls (MFCV 100.87 ± 5.1%, RMS 92.71 ± 11.84%).
CMT1A patients are not only weaker than healthy individuals in the knee extensors, but they also have impaired neuromuscular recovery after fatigue.
比较了 Charcot-Marie-Tooth 型 1A(CMT1A)患者和健康个体在上肢和下肢的疲劳任务后神经肌肉功能的恢复时间的影响。
在疲劳任务前(疲劳前 MVC)、疲劳后 10 秒(疲劳后 10 秒 MVC)和疲劳后 10 分钟(疲劳后 10 分钟 MVC),从 8 名 CMT1A 患者和 8 名匹配的健康个体中记录肘屈肌和膝伸肌的扭矩和表面肌电图(sEMG)数据肱二头肌和股外侧肌,在 80%MVC 下进行最大自主收缩(MVC)。
仅在下肢,疲劳前 MVC 时的扭矩和均方根 sEMG(RMS)较低(P<0.05)患者(91.93±45.95 Nm,0.11±0.07 mV)比对照组(161.06±75.5 Nm,0.24±0.16 mV)。在疲劳后 10 分钟 MVC 时,肌纤维传导速度(MFCV)和 RMS,以疲劳前 MVC 的百分比表示,低于(P<0.05)患者(MFCV 90.3±6.91%,RMS 84.50±9.89%)比对照组(MFCV 100.87±5.1%,RMS 92.71±11.84%)。
CMT1A 患者不仅在膝伸肌上比健康个体弱,而且在疲劳后神经肌肉恢复也受损。