Bai Juyi, a great poet in the Tang Dynasty, has a special liking for "Winter Xuan", a way of keeping in good health, and has gained great benefits from it. In his poem Negative Winter, he described the physical and mental experience of sunbathing in winter with delight: "Sitting with your eyes closed is good for your skin. At first, it was like drinking alcohol mash, and it was like being stung by Su. External integration is smooth, and Chinese integration is one. If you forget where you are, your heart is empty. " There is a lazy artistic conception in simplicity, which makes us yearn for it in our busy life. He can live to be 74 years old, which may be related to the "negative weather" in winter. Winter is the coldest season among the four seasons. The weather is freezing, the plants and trees are dying, the insects are infested, and all life is hidden. When talking about winter health care, Huangdi Neijing pointed out that "winter and March are closed, water and ice are dismantled, and there is no worry about the sun." If you go to bed early and get up late, you must wait for the sun ",that is, you should get up with the sun in winter." Sun Simiao, the "King of Medicine" in the Tang Dynasty, said in "Thousands of Women" that "when the weather is warm and there is no wind, let mother and son play in Japan and China for a few days, so that the blood will coagulate and the muscles will be tight, and the cold will not cause disease", and also clearly expounded the important role of sunbathing in preventing and treating diseases and promoting children's growth and development. Cao Cishan, a famous health care scientist in the Qing Dynasty, said in "The Old Man's Constant Words" that "sitting with your back to the sun, for example, is called the mystery of the negative sun, and the spine is slightly warm, which can make the whole body harmonious. The sun is the essence of the sun, and its light strengthens people's yang, and more clearly puts forward the health care function and scientific principle of "the mystery of negative sun". Warm sunshine in winter is precious. In my opinion, Dongyang is an inexhaustible natural health care product, which can adjust people's mood, cheer up their spirits, and improve the fun of life and work efficiency. At this time, we should seize the opportunity, cherish this rare winter sunshine, open the doors and windows in time, let the sunshine enter the room as a guest and enjoy the warmth of the sunshine. At the same time, when the sun is shining, you should also go out to bask in the sun, breathe fresh air, accept the baptism of winter sunshine and enjoy this free sunbathing. At this moment, even if you have a headache and brain fever, once you are treated by the winter sun, you will spend the severe winter healthily and safely.