Huang Tingjing first mentioned the theory of "Three Dantian" of China Qigong, which made great contributions to human health preservation. When practicing, pay attention to the downward flow of qi in the upper abdominal brain, middle abdominal heart and lower abdominal navel, and sink into the lower abdomen, which is the starting point and destination of luck. Protecting the abdomen, nourishing qi and refining essence are the highest hopes for people who read Neijing to cultivate physical strength, treat diseases, maintain health and live a long life.