What does “muscular endurance” refer to?

Muscular endurance specifically refers to the ability of a muscle or muscle group to sustain repeated contractions against resistance over an extended period. This characteristic is essential for activities that require maintaining a specific level of exertion without substantial fatigue for an extended duration, such as running, cycling, or performing high repetitions during weight training.

While the capacity to perform exercises for a long time relates to endurance, it does not specifically highlight the aspect of multiple contractions against resistance, which is central to muscular endurance.

Lifting heavy weights describes a different fitness aspect, known as strength, which emphasizes maximum force production rather than the ability to maintain performance over time. Similarly, maximum strength refers to the greatest amount of force a muscle can exert in a single effort, which also does not capture the essence of muscular endurance. Thus, focusing on repeated contractions against resistance is what accurately defines muscular endurance.