The best time to sunbathe to remove cold and damp is usually around 10 a.m., when ultraviolet radiation is low and sunlight is softer, which does not produce greater stimulation to human skin. Chinese medicine believes that the back is Yang, the heart and lungs are the main, the wind and cold evil into the body will lead to Yang injury, old and weak or long-ill body weaker people prone to recurrence of old diseases, thus aggravating the disease. The back of the sun can play a role in replenishing Yang Qi, can improve the Yang Qi weakness or Qi and blood deficiency patients prone to cold hands and feet phenomenon. In cold weather, sunbathing the back can also drive away the coldness of the spleen and stomach and help improve digestive function. As each person’s body metabolism is different, so the length of sunbathing also varies from person to person, young people can sunbathe for about 2 hours, while the elderly can sunbathe for half an hour a day. In addition, when sunbathing also need to pay attention to, it is best to wear vest-type clothing, while exercising sunbathing, rather than the entire back exposed to the sun, but easy to be sunburned.