title: The effect of glycerol on torque, electromyography, and mechanomyography.
abstract: 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 hyperhydration. 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.
authors.affiliation: Laboratory of Applied Physiology, University of Southern Mississippi, School of Human Performance and Recreation, Hattiesburg, MS 39406, USA. taeveto1@wsc.edu
authors.forename: Tammy K
authors.initials: TK
authors.lastname: Evetovich
authors.forename: Malcolm T
authors.initials: MT
authors.lastname: Whitehead
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Webster
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Soukup
authors.forename: Meir
authors.initials: M
authors.lastname: Magal
authors.forename: Lawrence C
authors.initials: LC
authors.lastname: Eschbach
authors.forename: Shawn M
authors.initials: SM
authors.lastname: Drake
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Boyd
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Weir
authors.forename: Kristi R
authors.initials: KR
authors.lastname: Hinnerichs
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001132:Arm / Q000502:physiology*; D001696:Biomechanical Phenomena; D003681:Dehydration / Q000503:physiopathology; D004576:Electromyography; D005260:Female; D005990:Glycerol / Q000008:administration & dosage*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology*; D009213:Myography / Q000379:methods*; D019415:Torque
chemical_list: D005990:Glycerol