"Flexibility is the ability to move a joint through its range of motion. Stretching exercises are effective in increasing flexibility and can allow people to more easily do activities that require greater flexibility. Adults should do flexibility exercises at least two or three days each week to improve range of motion. This can be done by holding a stretch for 10–30 seconds to the point of tightness or slight discomfort, repeating each stretch two to four times, and accumulating 60 seconds per stretch. Body composition is the percentage of the body composed of lean tissue, such as muscle, bone, and fluids, and fat tissue. Changes in body composition usually occur as a result of improvements in the other components of health-related physical fitness, as well as changes in eating habits. Other components of fitness related to sports performance include power, speed, agility, balance, and coordination."