What is commonly referred to as Muscle Mass?

Muscle mass refers to the total amount of muscle tissue in the body. Body composition encompasses the ratio of fat to lean mass, which includes muscle, bone, and water in the body. When discussing muscle mass, it is fundamentally tied to body composition because muscle is a significant component of lean body mass. Understanding body composition is crucial for assessing fitness, health, and performance, as it provides insight into how much muscle versus fat is present in an individual.

The other areas like core strength, flexibility, and cardiac output relate to specific physical attributes or functions but do not capture the concept of muscle mass directly. Core strength pertains to the stability and strength of the muscles around the trunk, flexibility is about the range of motion in joints, and cardiac output measures the heart's ability to supply blood to the body. While these are important aspects of fitness, they do not define muscle mass in the same way that body composition does.