THE EFFECT OF GLYCEROL ON TORQUE, ELECTROMYOGRAPHY, AND MECHANOMYOGRAPHY

• Published in: Journal of strength and conditioning research 2004-11, Vol.18 (4), p.741-746
• Main Authors: EVETOVICH, TAMMY K., WHITEHEAD, MALCOLM T., WEBSTER, MICHAEL J., SOUKUP, JEFFREY T., MAGAL, MEIR, ESCHBACH, LAWRENCE C., DRAKE, SHAWN M., BOYD, JOSEPH C., WEIR, JOSEPH P., HINNERICHS, KRISTI R.
• Format: Article
• Language: English
• Subjects: Adult; Analysis of Variance; Arm - physiology; Biomechanical Phenomena; Dehydration - physiopathology; Electromyography; Female; Glycerol - administration & dosage; Humans; Isometric Contraction - physiology; Male; Muscle, Skeletal - drug effects; Muscle, Skeletal - physiology; Myography - methods; Space life sciences; Torque
• ISSN: 1064-8011; 1533-4287
• DOI: 10.1519/00124278-200411000-00010

The purpose of this investigation was to determine the effect of hyperhydration on the electromyographic (EMG) and mechanomyographic (MMG) responses during isometric and isokinetic muscle actions of the biceps brachii. Eight (22.1 ± 1.8 years, 79.5 ± 22.8 kg) subjects were tested for maximal isometric, submaximal isometric, and maximal concentric isokinetic muscle strength in either a control (C) or hyperhydrated (H) state induced by glycerol ingestion while the EMG and MMG signals were recorded. Although fluid retention was significantly greater during the H protocol, the analyses indicated no change in torque, EMG amplitude, EMG mean power frequency (MPF), MMG amplitude, or MMG MPF with hyper-hydration. These results indicated that glycerol-induced fluid retention does not affect the torque-producing capabilities of a muscle, the impulses (EMG) going to a muscle, or muscular vibrations (MMG). It has been suggested that EMG and MMG can be used as direct electrical/mechanical monitoring, which could be presented to trainers and athletes; however, before determining the utility of these signals, the MMG and EMG responses should be examined under a variety of conditions such as in the present study.