How is "muscular endurance" best defined?

Muscular endurance is best defined as the ability of a muscle or group of muscles to perform repeated contractions over a period of time. This definition encompasses the concept that muscular endurance is not solely about how much weight can be lifted once, but rather about how long the muscles can sustain activity. It highlights the capacity of muscles to maintain exertion and to resist fatigue during extended physical tasks, facilitating activities such as distance running, cycling, or repetitive weight training.

The focus on repeated contractions emphasizes the critical aspect of endurance in fitness. While it may also relate to the muscle's ability to resist fatigue, this is more specifically a component within the broader context of performing repeated actions consistently over a period of time, distinguishing endurance from strength or power-focused training.