Usually the fitness instructor will remind you to warm up before exercise. The main purpose of this is to stretch the ligament, avoid the damage caused by large-scale movements, and also prevent muscle stiffness and cramps. However, there may not be many people who can stretch well. It takes at least 10- 15 minutes of practice to completely pull out the ligament. Similarly, stretching after high-intensity muscle strength training is also a relaxation way to relieve muscle tension. In this process, muscles become more elastic due to stretching, which is also an effective way to avoid varicose veins. In the gym, we can do the following stretching exercises on the flat ground or on a stretcher: 1. Stretch the ligament in sitting position: the chest is close to the knee, and the knee should not be bent. Feel pain in leg ligaments and back, stop stretching and take a deep breath twice, and slowly return to the initial action. Repeat the action 12 times. 2. Stretch the ligament horizontally: slowly pull up the stretched left leg without bending the knee, tighten the muscles of the buttocks and thighs until the thighs are at right angles to the body, then stop stretching, take a deep breath twice, and slowly return to the initial action. 3. Leg stretching: Stand up straight, open your feet shoulder width, open your toes in the direction of your legs, don't bend your feet, bend down, and touch your toes with your hands. I feel a stretch inside and behind my legs. 4. Step leg press: Open your feet left and right, bend one leg and squat, straighten the other leg, and press your body to the straight leg side. Alternate left and right legs during practice. 5, cross: put your hands in front of the ground, your legs are separated into a straight line, and your upper body is prone or sideways. 6, cross-legged: sit cross-legged, two feet opposite, hold your feet with both hands and lean forward.