when are the abdominal muscles involved in breathing
Muscles of respiration
The diaphragm is the major muscle responsible for breathing . It is a thin , dome - shaped muscle that separates the abdominal cavity from the thoracic cavity . During inhalation , the diaphragm contracts , so that its center moves caudally ( downward ) and its edges move rostrally ( upward ) . This compresses the abdominal cavity , raises the ribs upward and outward and thus expands the thoracic cavity . This expansion draws air into the lungs . When the diaphragm relaxes , elastic recoil of the thoracic wall causes the thoracic cavity to contract , forcing air out of the lungs . 
The diaphragm is the major muscle responsible for breathing . It is a thin , dome - shaped muscle that separates the abdominal cavity from the thoracic cavity . During inhalation , the diaphragm contracts , so that its center moves caudally ( downward ) and its edges move rostrally ( upward ) . This compresses the abdominal cavity , raises the ribs upward and outward and thus expands the thoracic cavity . This expansion draws air into the lungs . When the diaphragm relaxes , elastic recoil of the thoracic wall causes the thoracic cavity to contract , forcing air out of the lungs .
The diaphragm is the major muscle responsible for breathing. During inhalation, the diaphragm contracts, so that its center moves caudally (downward) and its edges move rostrally (upward).
The diaphragm is the major muscle responsible for breathing . During inhalation , the diaphragm contracts , so that its center moves caudally ( downward ) and its edges move rostrally ( upward ) .
During inhalation , the diaphragm contracts which compresses the abdominal cavity , raises the ribs upward and outward and thus expands the thoracic cavity. When the diaphragm relaxes, the cavity contracts , forcing air out of the lungs.
During inhalation , the diaphragm contracts , so that its center moves caudally ( downward ) and its edges move rostrally ( upward ) . This compresses the abdominal cavity , raises the ribs upward and outward and thus expands the thoracic cavity . When the diaphragm relaxes , elastic recoil of the thoracic wall causes the thoracic cavity to contract , forcing air out of the lungs .