Part A Once a motor neuron has fired, all the muscle fibers in a muscle contract. Submit Request Answer Provide. Feedback

When a motor neuron sends an electrical signal, it can activate multiple muscle fibers simultaneously, resulting in what’s known as a motor unit. This phenomenon is fundamental to muscle contraction and is why movements can be rapid and powerful. However, the strength and precision of this contraction can be modulated by the number of motor units recruited, leading to smooth and coordinated movements. In everyday activities, understanding how motor neurons and muscle fibers work together is valuable for optimizing workouts, rehabilitation, and even improving sports performance. For instance, athletes often train to enhance their neuromuscular efficiency, allowing them to engage more muscle fibers with each contraction, leading to better endurance and strength.