Both abdominal and thoracic respiration are forms of respiratory exercise. Abdominal respiration is a form of respiratory exercise in which changes in abdominal pressure and volume are transmitted to the thoracic cavity through the contraction and diastolic movements of the diaphragm and abdominal muscles, thereby affecting the expansion of the lungs. Thoracic respiration is a respiratory movement that affects the expansion of the lungs by changing the pressure and volume in the thoracic cavity through the diastolic and contraction of the intercostal muscles that cause the thorax to undulate. Abdominal breathing exercises are deeper than thoracic breathing exercises and can greatly improve the ventilation function of the lungs, but most people present thoracic breathing in a calm state, and abdominal breathing exercises after strenuous exercise. In some pathological states, only thoracic or abdominal breathing can occur, so the two types of respiratory movements can exist separately or simultaneously, or alternately, depending on the person’s physical state.