title: Mechanomyographic and electromyographic time and frequency domain responses during submaximal to maximal isokinetic muscle actions of the biceps brachii.
abstract: The purpose of this investigation was to determine the mechanomyographic (MMG) and electromyographic (EMG) amplitude and mean power frequency (MPF) versus torque relationships during isokinetic muscle actions of the biceps brachii. Twelve adults [mean (SD) age, 22.2 (2.7) years] performed submaximal to maximal isokinetic muscle actions of the dominant forearm flexors. Following determination of isokinetic peak torque (PT), the subjects randomly performed submaximal muscle actions in 20% increments from 20% to 80% PT. Polynomial regression analyses indicated linear increases in both MMG (r2=0.984) and EMG (r2=0.988) amplitude to 100% PT. There were no significant (P>0.05) relationships, however, for MMG and EMG MPF versus isokinetic torque. The results demonstrated similar responses for MMG and EMG in both the time and frequency domains. These findings suggested that simultaneous examination of MMG and EMG amplitude and MPF may be useful for describing the unique motor control strategies that modulate dynamic torque production. Furthermore, the results indicated that dynamic muscle actions can be used when applying techniques that require a linear EMG amplitude versus torque relationship.
authors.affiliation: Department of Nutrition and Health Sciences, Human Performance Laboratory, Center for Youth Fitness and Sports Research, University of Nebraska-Lincoln, Lincoln, NE 68588-0229, USA. tbeck@unlserve.unl.edu
authors.forename: Travis W
authors.initials: TW
authors.lastname: Beck
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Housh
authors.forename: Glen O
authors.initials: GO
authors.lastname: Johnson
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Weir
authors.forename: Joel T
authors.initials: JT
authors.lastname: Cramer
authors.forename: Jared W
authors.initials: JW
authors.lastname: Coburn
authors.forename: Moh H
authors.initials: MH
authors.lastname: Malek
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D000465:Algorithms; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004551:Elbow Joint / Q000502:physiology; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D019563:Mechanics; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D013314:Stress, Mechanical