Every cell in your body needs oxygen. When you inhale, air enters your lungs, and oxygen from the air moves to your blood. When you exhale, waste gas (mostly CO2) moves from your blood to the lungs to be breathed out. Inhaling and exhaling cause the lungs to expand and constrict repeatedly, like an elastic balloon that is being blown up then let out.
The lungs are supported and protected by muscles and bones. The diaphragm is the strong wall of muscle that separates your chest cavity from your abdominal cavity. When inhaling (‘inspiration’) the diaphragm contracts and the chest cavity enlarges, creating a vacuum that pulls air into the lungs. When exhaling (‘expiration’) the diaphragm relaxes and air is forced out of the lungs.
With age and lifestyle choices, lung function begins to change. This is due to several factors. Muscles weaken with age including the diaphragm. Elasticity is naturally lost in the lung tissue. The rib cage may tighten, leaving less room for the lungs to expand. While some reduction in lung capacity is normal with age, you can support your lungs by avoiding exposure to pollutants, exercising, supporting your immune system, and ensuring you have a well-balanced diet.1