The pursuit of immortality from ancient times to the present is a mirage, just a beautiful wish in people's hearts. But just as alchemy discovered mercury and divination invented the calendar, in the process of pursuing immortality, the ancients constantly explored and put forward various ideas of preserving health and eliminating diseases, which made indelible contributions to the extension of human life and the enhancement of physical function. Among them, Taoism is the best for health preservation, and Taoism pays attention to health preservation, practicing medical stone outside and elixir inside, praying for longevity, especially the understanding and maintenance of kidney. The Taoist health classic "Rejuvenation" has a detailed description of the related physiological functions of the kidney: it points out whether the male's energy and life span are normal. Has a lot to do with it. "Kidney governs storing essence". The kidney is full of water and young, while the essence is full of essence. "Frequent sexual intercourse" leads to renal failure, which leads to insufficient essence and easy fatigue.