Do we stand properly? If we don't, we need to, especially from a breathing standpoint. So many American's stand with hunched shoulders that restrict the breath from getting the needed long slow inhalation into the belly.
With hunched, rounded, or slouched shoulders we are preventing the breath from dropping into the belly.
This happens when the shoulders are hunched, setting up for the lower ribs to press into the belly, preventing the diaphragm from dropping down to bring air into the lower belly on the inhalation. This also is compressing the belly preventing large amounts of air to enter.
To stand properly we need to stand with a neutral spine. Neutral spine is with a concave lumbar part of the spine or lower back, convex thoracic part of the spine or middle back, and the concave cervical part of the spine or neck. With a neutral spine the belly sticks out a little as well as the butt, not like pictures in some magazines with sucked in belly and butts. Children up to the age of about four or five stand with a neutral spine until they pick up our western habits.
What we are working toward is the head over the heart, heart over the hips, hips over the knees, and knees over the ankles. This stacks the bones to hold the posture not the muscles,
which add to being tired, wore out, and fatigued since the muscles are holding us up and not our bones.
Once I was shown how to stand properly at the "Yoga on High" studio it took me about 3 months to convince my body this is what it needs to do. In the beginning standing with a neutral spine was not comfortable, since I'd spent my whole life standing wrong. My body was screaming at me to go back into a slouched position that it was so used to, but I kept working on it and now I have very little trouble at maintaining the neutral spine. I still find myself checking my posture to see if I'm standing properly at different times in the day, using the minds eye.
Start gradually, standing properly and over time you will feel better from the neutral spine and from the ease at which the breath comes in.