Henneman's size principle

Henneman's size principle explains how our nervous system recruits muscle fibers based on the intensity of activity. When a task is gentle, smaller, and more fatigue-resistant fibers are activated first. As more strength is needed, larger, faster-fatiguing fibers are gradually recruited. This organized pattern helps optimize energy use and prolong muscle endurance. In essence, the nervous system starts with the smallest units and adds larger ones as required, ensuring efficient and smooth muscle movements across different activity levels.