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Abdominal breathing means moving the diaphragm up and down. Because when inhaling, the diaphragm will drop and squeeze the organs below, so the stomach will expand, not the chest. Therefore, when exhaling, the diaphragm will rise higher than usual, so you can take a deep breath and spit out more carbon dioxide that is easy to stay at the bottom of the lung.
Generally, mammals use abdominal breathing. Its advantages are that it can give full play to the function of heart and lung cells, increase vital capacity, enhance heart function and increase the power of digestive system, thus enhancing and activating its function, which is conducive to eliminating the accumulation of toxins and the release of internal stress in the intestine. However, humans only use abdominal breathing when they are fetuses and babies. From the time they learn to walk, they change to local chest breathing. Due to the change of breathing mode, most lung cells are idle for a long time, losing their activity, making their vital capacity smaller, thus affecting people's life and potential. Most long-lived animals breathe on their bellies. Such as turtles and snakes. Why is abdominal breathing so relevant to life? Because all organs except the heart, brain and lungs are hidden in the abdominal cavity. Including the digestive system, hematopoietic system, reproductive system, secret urine system, endocrine system and lymphatic system, and there are a lot of blood vessels and nerves, so the abdominal cavity is very important. However, after human beings walk upright, chest breathing is dominant, and abdominal breathing begins to degenerate, which weakens abdominal movement, leading to easy accumulation of waste and slow blood flow. In severe cases, it will also affect the blood supply to the brain due to blood flow stenosis in the abdominal cavity. Therefore, it is very important to strengthen abdominal breathing and promote abdominal movement.