What typically occurs when muscles are repeatedly recruited?

When muscles are repeatedly recruited, they undergo stress and exertion that can lead to both pain and fatigue. This occurs because continuous use of muscles can cause microtears in the muscle fibers, which can result in inflammation and soreness—a condition commonly known as delayed onset muscle soreness (DOMS). Simultaneously, as muscles work repeatedly, they can become fatigued due to the depletion of energy sources, buildup of metabolic waste products, and the overall demand placed on them surpassing their recovery capabilities.

These processes often happen together; as muscles are used more frequently, the cumulative effects of fatigue can lead to discomfort or pain. In essence, the repeated recruitment of the muscles leads to an interplay between fatigue and pain as they respond to the demands placed upon them.