Foot bath is generally divided into hot water bath and cold water bath. We usually call water above 38℃ hot water. Soaking feet with hot water can clean the skin, promote blood circulation and dredge collaterals, and refresh the mind. Hot bath stimulation can directly reach the nerve center, which can excite the central nervous system, stimulate the sympathetic nerve, accelerate the heart rate and raise blood pressure. However, warm water at 36 ~ 38℃ can excite parasympathetic nerves and has sedative and hypnotic effects.

Hot water bath and medicinal bath have better effects on health care and disease prevention. Many diseases in traditional Chinese medicine are treated by the method of "external treatment of internal diseases", that is, the application of medicinal bath.

Cold showers are generally not used before going to bed, but in the morning, and the soaking time is generally no more than 2 minutes. After soaking, wipe your feet with a dry towel until they are red. Soaking feet in cold water also has a good regulatory effect on human body function: it can increase the function of central nervous system, strengthen the function of respiratory organs, improve disease resistance and enhance the function of digestive organs.