Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Impaired neuromuscular function during isometric, shortening, and lengthening contractions after exercise-induced damage to elbow flexor muscles
Author: Turner, T.
Tucker, K.
Rogasch, N.
Semmler, J.
Citation: Journal of Applied Physiology, 2008; 105(2):502-509
Publisher: Amer Physiological Soc
Issue Date: 2008
ISSN: 8750-7587
Statement of
Tanya S. Turner, Kylie J. Tucker, Nigel C. Rogasch, and John G. Semmler
Abstract: The purpose of this study was to examine the effect of exercise-induced damage of the elbow flexor muscles on steady motor performance during isometric, shortening, and lengthening contractions. Ten healthy individuals (age 22 ± 4 yr) performed four tasks with the elbow flexor muscles: a maximum voluntary contraction, a one repetition maximum (1 RM), an isometric task at three joint angles (short, intermediate, and long muscle lengths), and a constant-load task during slow (~7°/s) shortening and lengthening contractions. Task performance was quantified as the fluctuations in wrist acceleration (steadiness), and electromyography was obtained from the biceps and triceps brachii muscles at loads of 10, 20, and 40% of 1 RM. Tasks were performed before, immediately after, and 24 h after eccentric exercise that resulted in indicators of muscle damage. Maximum voluntary contraction force and 1-RM load declined by ~45% immediately after exercise and remained lower at 24 h (~30% decrease). Eccentric exercise resulted in reduced steadiness and increased biceps and triceps brachii electromyography for all tasks. For the isometric task, steadiness was impaired at the short compared with the long muscle length immediately after exercise (P < 0.01). Furthermore, despite no differences before exercise, there was reduced steadiness for the shortening compared with the lengthening contractions after exercise (P = 0.01), and steadiness remained impaired for shortening contractions 24 h later (P = 0.01). These findings suggest that there are profound effects for the performance of these types of fine motor tasks when recovering from a bout of eccentric exercise.
Keywords: motor function; electromyogram; acceleration; elbow flexion
RMID: 0020081976
DOI: 10.1152/japplphysiol.90421.2008
Appears in Collections:Physiology publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.