Muscle Strength, Motor Units, and Aging

Motor units are defined as the alpha motor neuron and all the muscle fibers that it innervates. The literature surrounding the role of the motor unit in modulating strength in the elderly is debatable, and it was the primary aim of this work to bring clarity to the topic. This book offers a comprehensive review of the literature involving motor unit quantification and strength outcomes as well as an experiment to bolster the notion of the number motor units affecting strength outcomes in the elderly. Motor unit quantification was performed using a novel technique, MUNIX (Nandedkar et al., 2004), and a reliability analysis was conducted to test the long term stability of the measurement.