Dantian Dantian explained: ① Acupoints, Guanyuan, Yinjiao, Qihai and Shimen are located under the belly button, which are all called Dantian. ② The part of the human body is called the upper abdomen between the eyebrows, the middle abdomen in the heart socket and the lower abdomen under the navel. (3) Taoism refers to three inches of human umbilical cord. To sum up, Tian Dan refers to Guanyuan point three inches below the navel. The concept of "Tian Dan" was originally a term used by Taoist Neidan School to cultivate the spirit, and now it has been widely quoted by various qigong schools. The book Treasure of Oriental Medicine quoted the words of Shenxian Jing, which not only pointed out the position of Tian Chan, but also expounded the function of Tian Chan: "The brain is the marrow sea and returns to Tian Chan; The heart is crimson fire, in the abdomen; Three inches below the navel is the lower abdomen. Xia Dantian, the house of Tibetan essence; Every day, the house of Tibetan gas; Go to the Tibetan Temple in Dantian. " The ancients called Yuanqi three treasures and regarded Dantian as the storage place of Yuanqi, so they attached great importance to the significance of Dantian and regarded it as "the foundation of life". As we know, intentional observance is a method and process for practitioners to concentrate their thoughts on a certain part or thing of themselves, help their consciousness to enter the static state of Qigong, and on this basis, give play to their conscious initiative, actively perceive and adjust their own functional activities, so as to achieve good results. Observing the abdomen intentionally is one of many ways for practitioners to concentrate their thoughts and stay in the abdomen. More precisely, this method belongs to the point method of observing one's own parts. But in practice, people's thoughts can't just stay at one acupoint, but only stay in a range centered on that acupoint. Therefore, it is more appropriate to understand Tian Chan as such a range. Although there are three fields and five fields, in practice, except for special circumstances, it is generally said that staying in the field is staying in the field. The ancients believed that Xia Dantian had the closest relationship with human life activities. It is the "ancestor of life", "source of qi", "root of internal organs", "root of the twelve meridians", "meeting of Yin and Yang", "breathing gate" and "land of fire and water", and it is the hub for the ascending and descending of Qi machine, and an important part for gathering, boiling and storing Qi. Of course, from the perspective of modern anatomy and physiology, Xia Dantian's part has not been found to have special shape and function so far. However, long-term practice has proved that staying in the abdomen can promote the practitioner's consciousness to achieve a quiet state and achieve curative effect. Its mechanism needs to be further studied and revealed. There are different opinions about where Tian Dan is. Most qigong experts believe that there are three types of dantian: upper dantian, middle dantian and lower dantian. The upper abdomen is called "Mud Pill", which is located at Baihui point on the top of the head, or Tang Yin point on the brow. Zhongdian Tian is called "Jianggong" and is located at the Zhongshan point in the chest. Xiadantian has a considerable volume in the lower abdomen, including Guanyuan, Qihai, Shenque, Mingmen and other acupoints. Others think that the abdomen is on the navel, which is the so-called ancestral orifices. Some people also say that the Juque point is Zhongdian Tian, also known as Lingtai. Xia Dantian is a spring in your palm. Opinions vary. The ancients believed that the abdomen is an important part of nourishing the whole body, so there is a saying that "no fire can warm all the bodies, and no water can moisten all the viscera", which is related to the life of the whole body. If there is an endless line, life will not die. " On the way to the Du Meridian, Shangdantian is the right place, the place where the yang is concentrated, the place where the gods hide, and the nerve center in charge of consciousness activities. This is the main part of practicing meditation. The function of Shangdantian is to exercise the nervous system, control one's own conscious activities, regulate and strengthen the nerve center, and inhibit the overall metabolic function, thus playing the role of energy storage. This helps to recuperate, save energy to fight diseases and get health. So it makes sense to feel stronger and more energetic after practicing. Attending the belly is in the head, and the head is the meeting of all yang. Patients with qi deficiency, head cold, cerebral anemia and low blood pressure can stay in the abdomen, but beginners should not stay in the abdomen immediately to avoid dizziness caused by qi exercise. Patients with excessive yang (such as heart fire, hyperactivity of liver yang and hypertension) should not stay in the abdomen for a long time. Zhong dantian is in the chest. If the patient is depressed with qi and the woman has menorrhagia, she can stay in the abdomen, but it is easy to cause chest tightness, so use it with caution. Xiadantian is the main part of Yunhua gas machine. Its function is to exercise the body fluid system and stimulate the energy substances in the body, so as to regulate and enrich the body fluid circulation and improve the overall metabolic function, thus playing an exciting role. It plays an important role in enriching the body, preventing premature aging, strengthening the body and prolonging life. Many qigong experts in past dynasties advocated the view of Dantian; Because this part is most closely related to human life activities, it is located in the center of the human body and is the starting point of Ren Duchong's Three Meridians Movement. The twelve meridians also enters the meridians directly or indirectly through the abdomen, and then enters the viscera. Xiadantian is the base for the lifting, opening and closing of Qi, and also the place where men hide essence and women raise babies. Difficult Classics holds that Xia Dantian is "the ancestor of life, the source of anger, the root of internal organs, the root of the twelve meridians, the meeting of Yin and Yang, the door of breathing, and the hometown where fire and water meet." Therefore, qigong experts often regard the abdomen as the main part of exercising, gathering and storing the true qi. Human vitality comes from the kidney and is hidden in the abdomen. Through the triple energizer, it flows throughout the body and promotes the functional activities of the five internal organs. The strength of the human body, life and death, depends entirely on the rise and fall of Tian Chan's vitality. Therefore, health care experts attach great importance to maintaining the vitality of dantian. If Tian Dan is full of vitality, it can mobilize people's potential and make the true qi circulate throughout the body. By observing the abdomen, we can regulate yin and yang, communicate with the heart and kidney, replenish qi and dredge eight veins, restore innate physiological functions, and promote good health and longevity.