Three warmings are alternating hot and cold baths. That is to say, the body is completely soaked in hot water to make it comfortable, so as to relax the blood vessels, and then washed with cold water to contract the subcutaneous blood vessels, so as to stop the body surface temperature from emitting. Because the body temperature is still high at this time, the metabolism is much stronger than usual, and the excess fat will be consumed, thus achieving the purpose of losing weight.