The resistance used in the light wheel tower of the instrument belongs to isometric contraction. In this type of contraction, the muscle keeps a relatively constant length under load, but the strength of muscle contraction is not enough to move the load. On the contrary, muscles in other parts of the body keep the posture of the body stable through resistance and provide resistance. In the light wheel tower, the distance between the pulley and the fixed point remains unchanged, but the resistance exerted by the rope or cable connected with the pulley needs to be countered and controlled by muscle contraction. This kind of exercise can train muscle endurance and stability.