Can abdominal breathing increase lung capacity?
Generally, abdominal breathing can increase lung capacity, but it is recommended to perform abdominal breathing under the guidance of a physician. The details are as follows:

Abdominal breathing is a form of respiratory movement caused by the contraction and relaxation of the diaphragm, which leads to movement of the abdominal wall. Compared with superficial chest breathing, abdominal breathing makes more complete use of pulmonary capacity, especially in the lower lobes of the lungs, helping to improve alveolar ventilation efficiency. Long-term regular practice of abdominal breathing can strengthen the power and endurance of respiratory muscles, gradually increasing the volume of gas exchange per breath, thereby expanding lung capacity to some extent.
In addition to increasing lung capacity, abdominal breathing improves respiratory efficiency by deepening breathing and reduces the risk of developing cardiorespiratory diseases. Furthermore, during abdominal breathing, the abdominal muscles alternately tense and relax, promoting the contraction and dilation of capillaries within the local muscles and accelerating blood circulation.
In daily life, maintaining regular physical exercise and healthy lifestyle habits is also recommended to help improve pulmonary function and increase lung capacity.