Hot compress can accelerate the circulation of body fluids, metabolism, lactic acid decomposition, relieve pain and rest. Just stop exercising and let the excess lactic acid be absorbed by itself, and the stretching of muscle fibers will automatically recover. The pain will go away in about 5 days, so massage. Effective massage can also promote better blood circulation when muscles are sore and stiff, so that the damaged muscle tissues of the body can be better metabolized and recovered. This can be done before and after exercise.