Brandenberger Kyle J, Rawdon Chris L, Armstrong Erica, Lonowski Jacob, Cooper Lakee'dra
Departments of Respiratory Therapy & Physical Therapy, Georgia State University, Atlanta, GA, USA.
Department of Exercise Science, Mercer University, Macon, GA, USA.
J Rehabil Assist Technol Eng. 2023 Apr 3;10:20556683231164339. doi: 10.1177/20556683231164339. eCollection 2023 Jan-Dec.
An electrically stimulated intermittent fatigue test using mechanomyography was recently proposed as a possible tool for detecting clinically relevant changes in muscle function. This study was designed to determine whether the proposed test can detect additional fatigue when it should be present. Subjects ( = 10) underwent two trials each (occluded and normal blood flow) with a standardized fatigue protocol on the Ankle Dorsiflexors (AD) and Wrist Extensors (WE) using a clinical electrical stimulator. Mean normalized twitch acceleration was strongly predictive of mean normalized torque ( = 0.828). The WE experienced lower twitch magnitudes throughout the tourniquet trial (10.81 ± 1.25 m/s) compared to normal blood flow (18.05 ± 1.06 m/s). The AD twitches were overall reduced in the tourniquet trial (3.87 ± 0.48 m/s) compared with the control trial (8.57 ± 0.91 m/s). Occluding blood flow to a muscle should cause greater muscle fatigue. The ability to detect reduced contraction magnitudes during an electrically stimulated fatigue protocol resulting from low blood flow suggests the proposed test may be capable of detecting clinically relevant muscle deficits.
最近有人提出，使用肌机械图进行电刺激间歇性疲劳测试可能是检测肌肉功能临床相关变化的一种工具。本研究旨在确定所提出的测试在应该出现额外疲劳时是否能够检测到。受试者（n = 10）使用临床电刺激器，对踝背屈肌（AD）和腕伸肌（WE）按照标准化疲劳方案各进行两次试验（血流阻断和正常血流）。平均标准化抽搐加速度对平均标准化扭矩具有很强的预测性（r = 0.828）。与正常血流情况（18.05±1.06米/秒）相比，在止血带试验期间，WE的抽搐幅度较低（10.81±1.25米/秒）。与对照试验（8.57±0.91米/秒）相比，在止血带试验中，AD的抽搐总体上有所减少（3.87±0.48米/秒）。阻断肌肉血流应会导致更大的肌肉疲劳。在由低血流引起的电刺激疲劳方案期间检测到收缩幅度降低的能力表明，所提出的测试可能能够检测到临床相关的肌肉缺陷。
