The diaphragm is the main muscle for breathing. It sits right beneath the lungs, is shaped like a dome, and separates the chest from the abdomen.
When we inhale, the diaphragm contracts down and descends into the abdominal cavity. This along with the ribcage moving out, creates space in the thoracic cavity – chest. The lungs expand and the air pressure inside the lungs decreases below the air pressure outside the body. Since gasses move from a region of high pressure to a region of low pressure, air rushes into your lungs.
When we exhale, the opposite happens. The diaphragm relaxes up. The ribcage closes down. The lungs shrink. The air pressure inside the lungs rises above the one outside the body. Air rushes out.
Now imagine how many times this up and down movement happens in your body during a day. About 40,000 times!
Let’s go back to the diaphragm moving down into the abdominal cavity during inhalation. This movement creates intra-abdominal pressure stabilizing the body supporting the spine and the pelvis. Hence the tendency to inhale and hold your breath, as you’re lifting something heavy.
When you breathe through your nose, it’s easier to engage your diaphragm. The air goes deeper into the lungs leading to better oxygenation of the blood. At the same time, the diaphragm supports your posture and functional movement.
All in all, breathing is essential. It's powerful. And it’s worth every effort to do it correctly!
Stay healthy, stay happy.