The principle of foot patch is very simple, just like doing foot massage. Massage is to press the acupoints of foot patch through knuckles, and foot patch is to stimulate the acupoints of foot patch through medicine bags, dredge meridians and promote blood circulation, so as to achieve the purpose of detoxification, dampness elimination and health promotion. When the body is smooth, there will be fewer natural problems. That's it. It is suggested to use the foot patch reasonably, not blindly.