Ye Xin, Gockel Nathan, Vala Daniel, Devoe Teagan, Brodoff Patrick, Gaza Victor, Umali Vinz, Walker Hayden
Department of Rehabilitations Sciences, University of Hartford, West Hartford, CT 06117, USA.
Sports (Basel). 2022 Sep 5;10(9):134. doi: 10.3390/sports10090134.
This study aimed to examine the potential sex differences in wide-pulse high-frequency neuromuscular electrical stimulation (WPHF NMES)-evoked force. Twenty-two subjects (10 women) completed this study. Prior to the stimulation, the visual analogue scale (VAS) for discomfort and the rating of perceived exertion (RPE) were measured, followed by the isometric strength of the dominant elbow flexor muscles. The subjects then completed ten, 10-s on 10-s off WPHF NMES (pulse width: 1 ms, frequency: 100 Hz) at maximum tolerable intensities. The subjects' RPE was recorded after each set, and the VAS was measured following the last stimulation. The stimulation induced significant increase in discomfort for both sexes, with women having greater discomfort than men (men: 22.4 ± 14.9 mm, women: 39.7 ± 12.7 mm). The stimulation amplitude was significantly greater in men than in women (men: 16.2 ± 6.3 mA, women: 12.0 ± 4.5 mA). For the evoked force, only the relative NMES-evoked force was found greater in women than in men (men: 8.96 ± 6.51%, women: 17.08 ± 12.61%). In conclusion, even at the maximum tolerable intensity, WPHF NMES evoked larger relative elbow flexion force in women than in men, with women experiencing greater discomfort.
本研究旨在探讨宽脉冲高频神经肌肉电刺激（WPHF NMES）诱发力量方面潜在的性别差异。22名受试者（10名女性）完成了本研究。在刺激前，测量不适视觉模拟量表（VAS）和主观用力感觉评分（RPE），随后测量优势侧肘屈肌的等长力量。然后，受试者以最大可耐受强度完成十组10秒开、10秒关的WPHF NMES（脉冲宽度：1毫秒，频率：100赫兹）。每组刺激后记录受试者的RPE，并在最后一次刺激后测量VAS。刺激导致两性的不适感均显著增加，女性的不适感高于男性（男性：22.4±14.9毫米，女性：39.7±12.7毫米）。男性的刺激幅度显著大于女性（男性：16.2±6.3毫安，女性：12.0±4.5毫安）。对于诱发力量，仅发现女性的相对NMES诱发力量大于男性（男性：8.96±6.51%，女性：17.08±12.61%）。总之，即使在最大可耐受强度下，WPHF NMES诱发的女性相对肘屈力量也大于男性，且女性的不适感更强。
