Exercise Training and Motor Unit Discharge Behavior
Department of Kinesiology, University of Massachusetts
Last modified: April 28, 2007
Presentation date: 08/12/2007 11:50 AM in MCC
Changes in muscle characteristics are well-recognized following resistance exercise training. However, we now know that there are numerous neural and neuromuscular adaptations that may also occur in both young and older adults. As the ''final common pathway'', the study of human motor unit discharge behavior allows us to document these adaptations. Motor unit firing rate is amenable to change in older individuals, and we know that brief periods of resistance training produce increases in motor unit firing rates, likely attributable to changes in central drive. Doublet firing may improve muscular force production by utilizing the features of the ''catch'' principle and we know that doublet firing increases with training and is lower in older adults. The anecdotal literature suggests that motor unit synchronization might improve with exercise training, however, actual studies involving motor unit discharge behavior produce equivocal results regarding motor unit synchronization. These and other motor unit behavioral features will be discussed in this presentation.