What defines muscular strength?

Muscular strength is primarily defined as the maximum amount of force that a muscle or group of muscles can exert in a single effort against a resistance. This definition highlights the importance of generating a high level of force in a brief, single contraction, which is crucial for activities such as weightlifting, sprinting, or any task that requires a powerful burst of strength.

The other answer choices refer to different aspects of physical fitness. Endurance is related to how long the muscles can perform without fatigue, which is not the same as strength. The total weight a person can lift is a measure of strength but is more about a cumulative capability rather than the specific definition of strength itself. Flexibility pertains to the range of motion of the muscles and joints, which does not relate to the concept of muscular strength directly.