The principle of scalding feet is to heat the feet with hot water, and then slowly the qi and blood of the human body begin to accelerate and gradually sweat, which is also a manifestation of the acceleration of qi and blood. Young people can, but old people should pay attention. The old man depends on his physical condition! According to Neijing, we must try not to "leak skin" in winter, because people are very weak at this time, and it is easy to make the yang dissipate more, that is, "take away the qi". Burning feet means that people sweat a lot and their skin leaks badly. I felt very comfortable at that time, and I often felt weaker the next day. Therefore, for the elderly and frail patients, it is best not to choose this health care method.