Which term refers to the range of motion at a joint?

Flexibility is the term that specifically refers to the range of motion at a joint. It is defined as the ability of a muscle or muscle groups to lengthen passively through the range of motion. Greater flexibility allows for a more extensive movement around a joint, which is crucial for various physical activities and can help prevent injuries.

In contrast, other terms like agility relate to the ability to move quickly and change direction efficiently, balance pertains to the ability to maintain the body's center of mass over its base of support, and muscular strength refers to the maximum amount of force a muscle or muscle group can produce. Each of these concepts is important in physical fitness, but flexibility directly addresses the aspect of joint range of motion.