Starting posture: take a unilateral kneeling posture, and the distance between the front and rear feet is 90 degrees from the knees. Stand on tiptoe to improve your body, with your hands akimbo and your upper body straight. Action: front and back thighs, back calves, gluteus maximus. Second, the starting position of the shoulder muscles: the elastic rope is fixed below the hip, the elastic rope is held in the hand, the hands are open at the sides of the body, and the elbow is slightly lower than the shoulder. Action: Keep your back straight and push your hands up, but don't straighten your elbows completely.