1) Diaphragmatic breathing uses the diaphragm, a dome-shaped muscle located between the lungs and stomach, to drive breathing. 2) When inhaling, the diaphragm contracts and flattens, increasing the volume of the chest cavity and lungs. When exhaling, the diaphragm relaxes and rises upward. 3) Most people do not use their diaphragms fully when breathing, instead relying more on shallow chest breathing. Learning diaphragmatic breathing can help improve breath control and lung capacity.