According to Dr. Chad Walding, Doctor of Physical Therapy and Co-Founder of NativePath, “The diaphragm is a dome-shaped muscle that plays a major part in your breathing.”
Where most people breathe very shallow—with their chest rising and falling—you want to train yourself to breathe deeply—with your belly rising and falling.
Dr. Walding explains it like this: “When you inhale like you were designed to—from your diaphragm—your belly will rise (causing your belly button to move away from the spine). And when you exhale, your belly will fall. What you’ll notice as you belly breathe is that your chest stays relatively still.”
Put another way, when you inhale while belly breathing, your diaphragm contracts so that your lungs can expand to let in extra air.
“This is the way your body wants to breathe,” says Walding. “It’s what increases oxygen and maintains proper levels of CO2. When your body gets more air, you feel better.”