Male 18 excellent. Female 23 is excellent. Track and field sports can easily cause injuries to muscles, joints and ligaments, especially lower limbs. The only way to prevent it is to prepare before the game. The more prepared you are, the less likely you are to get hurt. On the basis of jogging, you can exercise the muscles of shoulder joint, elbow joint, back and waist, legs, knees and ankles, strengthen the strength of muscle ligaments, improve the sensitivity and coordination of the body, thus preventing injuries and improving sports performance. It is very important to master the correct breathing method. In the middle and long-distance running, in order to increase the lung ventilation, the method of synchronous breathing of nose and mouth is used when breathing. The breathing rhythm should match the running rhythm, generally using two steps and one breath, two steps and one breath, or three steps and one breath. Pay attention to increase the depth of breathing when breathing.