Correct Abdomen Positioning
Notice in this illustration the movement of the abdomen when inspiration occurs.
The diaphragm should lower and the lungs should not expand outward, but downward.
Correct posture of the shoulders and chest area will allow for supportive breathing.
When the head is also in correct position, the air flows freely from the abdomen during exhalation.
Basics of Posture or more information on Head positioning.