breathing in which most of the respiratory effort is done by the abdominal muscles; "abdominal breathing is practiced by singers"

Abdominal breathing is a term used to describe a state where the main mechanism of breathing, that is to say changes in the intrathoracic volume and intrapleural pressure, is largely provided by the diaphragm, intercostal muscles and to a limited extent by abdominal muscles. It may be due to increased work of breathing secondary to deficits in the muscles of respiration or pulmonary function or may be physiological as is practiced by some singers.