NEUROMUSCULAR ADAPTATIONS IN EXERCISE SCIENCE 749

Abstract

This symposium will review the growing evidence that demonstrates the potential for adaptation and plasticity in the human neuromuscular system. The segmental control system presents an excellent model for the study of adaptations resulting from either motor learning or exercise training. Reggie Edgerton will discuss a model which demonstrates the possibilities of learning-induced changes in spinal centers. Adaptations in segmental reflex processing, including changes in H-reflexes and crossed spinal reflexes will be discussed by David Koceja. Muscle fatigue also comparises a useful model for the study of short-term neuromuscular adaptation. Fatigue can be caused by a number of different mechanisms that result in a reduced ability to perform a motor task. The dominant mechanism appears to be task-dependent and the task dependency hypothesis of muscle fatigue will be presented by Roger Enoka. Finally, increasing evidence suggests that the manner in which the nervous system controls motor unit activation can be altered as a result of aging and exercise. Gary Kamen will discuss adaptations to motor unit discharge behavior, including possible changes in motor unit firing rate and motor unit synchronization.