lie supine.
Gently place your left or right hand on your navel.
When you inhale, direct the air towards your abdomen.
If you do this inhalation step correctly, your hand will be lifted by your abdomen.
The deeper you inhale, the higher your abdomen rises.
As the abdomen expands, the diaphragm descends.
Now exhale, and you will find that your abdomen is retracted inward and towards your spine.
You can exhale all the air out of your lungs by contracting your abdomen as much as possible.
And in doing so, the diaphragm naturally rises.
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