|MadSci Network: Anatomy|
Hi junyoung. Chances are, your chest does expand during inhalation also, just not as noticeably as your belly. It has to, or there would be very little room for the air. Your belly expands, though, because you aren't properly supporting your breathing with your diaphragm. When this happens, the top of the diaphragm moves down in order to create space for your lungs to expand. This method of breathing pushes your abdominal organs out of the way, and they have to go somewhere. So, everything bellies out front. This is not the proper action of the diaphragm, and, incidentally, is why a lot of people who aren't overweight, don't drink, and aren't middle-aged have a beer belly or a spreading abdomen. Check out the site at the bottom for more information on the matter. It's not too late to change your habits. =) Thanks, Justin Miller http://www.alexander works.org.uk/breathing.html
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