Abdominal or diaphragmatic breathing is practiced by enhancing the action of the diaphragm and minimizing the action of rib cage.
The diaphragm is a domed sheet of muscle that separates the lungs from the abdominal cavity and, when functioning correctly, promotes the most efficient type of breathing.
During inhalation the diaphragm moves downward, pushing the abdominal content downward and outward. During exhalation the diaphragm moves upward and the abdominal contents move inward.
Movement of the diaphragm signifies that the lower lobes of the lungs are being utilized. The proper use of the diaphragm causes equal expansion of the alveoli, improves lymphatic drainage from basal part of lungs , massages the liver, stomach, intestine and other organs that lie immediately beneath it, expert a positive effect on the cardiac function and coronary supply, and improves oxygenation of the blood and circulation.