The Yellow Emperor's Neijing has a discussion about keeping in good health at four seasons, that is, nourishing yang in spring and summer, which is called Xia Zhishi in spring. The yang in nature is rising, so the health-preserving person should preserve it in time to maintain the yang in the body and keep it abundant. At this time, any situation that consumes the yang and hinders the smooth flow of the yang should be avoided.

Huangdi Neijing is divided into Lingshu and Suwen, which is the earliest medical classics in China and one of the four classic works of traditional medicine. Huangdi Neijing is a comprehensive medical work, which established the five-element theory, pulse theory, zang-xiang theory, meridian theory, etiology theory, pathogenesis theory, symptoms, diagnosis method, treatment, health preservation theory and luck theory of traditional Chinese medicine.