Carbon dioxide discard rate measurement is linked to the ability to control the diaphragm and engage the parasympathetic nervous system.

“what carbon dioxide discard rate is tapping into is your ability to mechanically control your diaphragm certainly that's one aspect of it, but that relates in a very direct way to your ability to put the brake on your stress system. To engage the so-called parasympathetic or calming arm of your autonomic nervous system.”