Health-related fitness refers to the five components of physical fitness directly related to good health, as opposed to athletic ability. These components are cardiovascular endurance, flexibility, muscular strength, muscular endurance and body composition.
Cardiovascular endurance allows the body to use the circulatory and respiratory system efficiently to enable aerobic metabolism. Flexibility is essential to improve the range of motion of joints to avoid injury. Muscular strength refers to steadily increasing the amount of force exerted by the muscles. Muscular endurance delays the onset of fatigue. Body composition refers to the relative amount of fat to lean tissues in the body. It helps gauge fitness levels better than just weight alone.