Motor unit firing rates during constant isometric contraction: establishing and comparing an age-related pattern among muscles
Eric A. Kirk, Anita Christie, Christopher A. Knight, Charles L. Rice
Abstract
The mean frequency of motor unit firing rates were compared systematically among several muscles and between young and older adults from new and published data sets. Firing rates among muscles were lower and more similar during voluntary isometric contraction in older than younger adults. Firing rate responses from voluntary contraction intensity were muscle dependent and more dissimilar among muscles in the older than young adults.
Topics & Concepts
Isometric exerciseMotor unitContraction (grammar)Motor unit recruitmentTurnoverMuscle contractionElectromyographyPhysical medicine and rehabilitationMedicineAnatomyPhysical therapyInternal medicineEconomicsManagementMuscle activation and electromyography studiesMotor Control and AdaptationChildren's Physical and Motor Development