Exercise is physical activity that is planned, structured, and repetitive for the purpose of conditioning any part of the body.Exercise is used to improve health, maintain fitness and is important as a means of physical rehabilitation. Exercise is useful in preventing or treating coronary heart disease, osteoporosis, weakness, diabetes, obesity, and depression. Range of motion is one aspect of exercise important for increasing or maintaining joint function. Strengthening exercises provide appropriate resistance to the muscles to increase endurance and strength.