Find out more about the lungs and breathing process. This makes the chest cavity bigger and pulls air through the nose or mouth into the lungs. To breathe out (exhale), your diaphragm and rib cage muscles relax. This naturally lets the air out of your lungs. To get the oxygen your body. Learn about your lungs and respiratory system, how your muscles and moves from your blood to the lungs and is exhaled (breathe out). Your diaphragm loosened up and moved back up into your chest cavity. They're still trying to get air into your lungs, but the lack of. Thoracentesis is a procedure to remove fluid or air from around the lungs. A needle is put through the chest wall into the pleural space. In the same way, when the diaphragm relaxes the chest cavity decreases, and air is pushed out of the lungs, and we exhale. When you pulled. COPD (chronic obstructive pulmonary disease) is a long-term illness that makes it hard to breathe. When you have COPD, air does not flow easily into and out. During breathing, these muscles normally tighten and pull the rib cage up. Your chest expands and the lungs fill with air. It includes your airways, lungs and blood vessels. Diaphragm: Muscle that helps your lungs pull in air and push it out. At the same time, the muscles between your ribs pull your rib cage up and out. This expands the chest and draws air into the lungs. Air is pulled into your.