Electrically induced torque decrease reflects more than muscle fatigue. Issue 4 (30th August 2014)

• Record Type: Journal Article
• Authors: Papaiordanidou, Maria; Stevenot, Jean‐Damien; Mustacchi, Valerie; Vanoncini, Michele; Martin, Alain
• Is Part Of: Muscle & nerve. Volume 50:Issue 4(2014:Oct.)
• Page Start: 604
• Page End: 607
• Publication Date: 2014-08-30
• Subjects: Neuromuscular diseases -- Periodicals; Muscles -- Periodicals; Nerves -- Periodicals; 616.74
• DOI: 10.1002/mus.24276
• Languages: English
• ISSNs: 0148-639X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>The aim of the study was to compare the fatigue induced by different electrical stimulation (ES) protocols. The triceps surae muscle of 8 healthy subjects was fatigued with 4 protocols (30 H<sc>z</sc>−500 μs, 30 H<sc>z</sc>−1 ms, 100 H<sc>z</sc>−1 ms, and 100 H<sc>z</sc>−500 μs), composed of 60 trains (4 s on–6 s off), delivered at an intensity evoking 30% of maximal voluntary contraction (MVC). Fatigue was quantified by ES and MVC torque decreases. The amplitude of the twitch delivered at the intensity and pulse width used in each fatiguing protocol (twitch at I_stim) was analyzed. All parameters decreased significantly after all protocols. The ES torque decrease correlated positively with the twitch decrease elicited at I_stim only for the 30‐H<sc>z</sc> protocols. Results show that, during the 100‐H<sc>z</sc> protocols, phenomena not related to the fatigue of the solicited motor units may occur, including changes in the excitability threshold of the axonal terminal branches. <italic>Muscle Nerve</italic> 50: 604–606, 2014</p> </abstract>