Breath is distinct from what is often called 'belly breathing.'
breathing focuses simply on the movement of the belly with the breath
-- expanding on the inhalation, contracting with the exhalation
-- as an aid to deepening the breath. This is often taught to people
who breathe primarily with the secondary muscles of the upper chest;
it's easy to feel the movement of the belly with the breath, and
so it is a fairly simple matter to repattern one's breathing by
drawing the breath deeper -- into the belly.
diaphragmatic breathing is a more precise -- and beneficial -- practice,
when understood properly. Diaphragmatic breathing is 'three-dimensional,'
involving all sides of the lower ribs, and not just the belly. It
is done with the middle of the torso, involving a gentle expansion
of the lower ribs as the diaphragm draws downward.
breathing can be practiced by placing your hands at the sides of
the lower ribs. Breathe into your belly and lower ribs, expanding
three-dimensionally against the gentle resistance of your hands
in order to tune into and strengthen the workings of the diaphragm.
Your belly, though it does expand at first with the breath (signaling
the downward movement of the diaphragm that draws in the breath)
it should not distend above the ribs on the inhalation.
in diaphragmatic breath the belly does move out at first with the
inhalation as it does with belly breathing, the two are not the
same. With diaphragmatic breathing, you'll notice that as the breath
continues to expand with the movement of the ribs and diaphragm,
the lower belly tones inward and even draws slightly upward, even
as the diaphragm remains fully expanded. Consciously include the
expansion of the lower ribs with your breath; this keeps the belly
and solar plexus toned properly, rather than distended.
belly breathing can sometimes stir up deeply held emotions -- and
has its usefulness for that reason -- diaphragmatic breathing brings
calmness and tranquility and soothes troubled emotions. Diaphragmatic
breathing brings the breath in deep while massaging the heart and
toning and nourishing your internal organs.
practicing diaphragmatic breathing in times of stress and anxiety,
as well as at the beginning of every pranayama practice!