How breathing works?

When the lungs take a breath in, they expand – but they can’t do this on their own. To make them suck in air, the lungs are pulled open by the muscles around them. Then, to breathe out, the muscles relax and the lungs become smaller again, so air is squeezed back out. The muscles used for breathing are the diaphragm, which is below the lungs, and the intercostals muscles, between the ribs.

Breathe in and out

To breathe in, muscles between the ribs contract, pulling the ribcage upwards and outwards. At the same time, the diaphragm, a strong sheet of muscle below the lungs, tightens, pulling the lungs down. The lungs expand and suck in air.

To breathe out, the rib muscles and diaphragm relax again. This makes the ribcage fall back down, while the diaphragm moves upwards. The lungs are squeezed and become smaller, pushing air back out.

Air enters through mouth and nose. As the ribcage is pulled up and out, the chest expands. The lungs enlarge to fill the larger space in the chest. The diaphragm contracts, pulling the bottom of the lungs down.

Air leaves the body. The falling ribcage pushes the lungs down and in. The rib and chest muscles relax, tilting the ribs downwards. The lungs are made smaller, forcing out air. The diaphragm relaxes and becomes longer and more flexible.


Picture Credit : Google