fatigue-related motor unit recruitment

Fatigue-related motor unit recruitment refers to how your nervous system responds when your muscles get tired. Normally, your brain signals your muscles to contract by activating motor units, which are groups of muscle fibers and their controlling nerves. When muscles fatigue, they become less effective, so your brain ramps up recruitment, activating more or alternative motor units to maintain force. This process helps you continue movement despite fatigue, but over time, it can lead to increased effort and a feeling of tiredness as the system compensates for reduced muscle efficiency.