The benefits of stretching on the human body mainly include helping teenagers grow and develop, relaxing muscles to relieve fatigue and so on. 1. Promote growth and development: if teenagers often stretch, can give the epiphysis a certain pressure, good for its growth and development, stretching after moderate activities, help teenagers grow and develop, for the growth of bones is good. 2. Relaxation of muscles to relieve fatigue: for the sedentary and standing crowd, moderate stretching can help to relax the long-term tense muscles, such as the waist and back muscles, shoulder and neck muscles, etc., so that muscle relaxation, improve the muscles and joints, to restore the normal function of the joints, to improve the blood supply of the muscle ligament, and at the same time, can also alleviate fatigue. Although stretching has benefits, but should be measured, moderate stretching, not the more vigorously the better, excessive stretching will cause muscle strain or even tear, serious cases may also lead to ligament rupture and other dangers, therefore, should be in the sports rehabilitation physician under the guidance of the stretching exercise to improve the function of muscles and ligaments.