Vieira Denis César Leite, Vieira Amilton, Dos Santos Matheus Avelino, Da Cunha Rafael Rodrigues, Lage Victor, Blazevich Anthony J, Bottaro Martim
College of Physical Education, University of Brasilia, Federal District.
Centre for Exercise and Sports Science Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup.
Eur J Transl Myol. 2021 Dec 7;31(4):10045. doi: 10.4081/ejtm.2021.10045.
Vibratory (Tvib) and sustained (Tsust) torque responses to concurrent Achilles tendon vibration and neuromuscular electrical stimulation applied over the muscle belly (vib+stim) are used as indicators of motoneuron facilitation and, theoretically, persistent inward current strength. However, neuromuscular electrical stimulation (NMES) applied to the nerve trunk may potentiate motoneuronal excitability more than muscle belly NMES, yet it remains unclear whether NMES applied over the nerve evokes robust Tvib and Tsust responses when used during the vib+stim protocol. This study tested whether a nerve-targeted vib+stim protocol elicits Tvib and Tsust responses in the ankle plantar flexors with acceptable intra- and inter-session reliability. Fifteen men performed the vib+stim protocol with NMES applied over the tibial nerve three times across two sessions; twice in a single session (5-min apart) to test intrasession reliability and then again after 48 h to test intersession reliability. Intraclass correlation coefficients (ICC3,1), within-participant coefficients of variation (CV) and pairwise comparisons were used to verify relative and absolute reliability as well as systematic bias. Thirteen men presented Tvib and Tsust responses (response rate of 87%). Intrasession Tvib and Tsust ICCs were >0.73 but inter-session ICCs were <0.5. Although no systematic bias was detected (p>0.05), both intra- and inter-session CVs were large (>10%) for Tvib and Tsust. The Vib+stim protocol with NMES applied over the nerve evoked Tvib and Tsust in almost all participants, but presented a large intra- and inter-session variability. The method does not appear to be effective for assessing motoneuron facilitation in the plantar flexors.
将跟腱振动与作用于肌腹的神经肌肉电刺激(振动 + 刺激)同时施加时的振动(Tvib)和持续(Tsust)扭矩反应,用作运动神经元易化的指标,从理论上讲,也是持续内向电流强度的指标。然而,施加于神经干的神经肌肉电刺激(NMES)可能比肌腹NMES更能增强运动神经元的兴奋性,但在振动 + 刺激方案中使用时,施加于神经的NMES是否能引发强烈的Tvib和Tsust反应仍不清楚。本研究测试了一种针对神经的振动 + 刺激方案是否能在踝跖屈肌中引发Tvib和Tsust反应,且具有可接受的组内和组间可靠性。15名男性在两个时间段内分三次进行了将NMES施加于胫神经的振动 + 刺激方案;在单个时间段内进行两次(间隔5分钟)以测试组内可靠性,然后在48小时后再次进行以测试组间可靠性。使用组内相关系数(ICC3,1)、参与者内部变异系数(CV)和成对比较来验证相对和绝对可靠性以及系统偏差。13名男性出现了Tvib和Tsust反应(反应率为87%)。组内Tvib和Tsust的ICC大于0.73,但组间ICC小于0.5。尽管未检测到系统偏差(p>0.05),但Tvib和Tsust的组内和组间CV都很大(>10%)。将NMES施加于神经的振动 + 刺激方案在几乎所有参与者中都引发了Tvib和Tsust,但组内和组间变异性很大。该方法似乎对评估跖屈肌中的运动神经元易化无效。