Which of the following describes flexibility?

Flexibility specifically refers to the range of motion of joints and the ability of muscles to elongate and stretch. This characteristic is essential for overall physical function and plays a critical role in athletic performance, injury prevention, and daily activities. Good flexibility allows for the execution of movements with greater ease and efficiency, enhancing performance in sports and reducing the risk of strains or injuries.

The other options describe different aspects of physical fitness and health; for instance, the total weight of the body deals with body composition, the ability to resist fatigue pertains to muscular endurance, and the strength of the heart relates to cardiovascular fitness. Each of these presents an important component of overall health and fitness, but none capture the specific definition of flexibility.