How to measure your lung capacity

  • The maximum amount of air you can breathe in and out is your vital lung capacity. Everybody’s vital lung capacity is different depending on factors such as their age and fitness levels.

  • When you breathe in and out, the air pressure inside our lungs changes, allowing oxygen to enter or carbon dioxide to leave.

  • The larger your lung capacity the more oxygen can be breathed in and transported around the body.

Have a go

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What happens when we inhale?

  1. The muscles between the ribs contract and the rib cage lifts.
  2. The diaphragm contracts and moves downwards.
  3. The volume inside the chest increases.
  4. The pressure inside the chest decreases and air is pushed into the lungs through the mouth.

What happens when we exhale?

  1. The muscles between the ribs relax allowing the rib cage to return to its resting position.
  2. The diaphragm relaxes and moves upwards.
  3. The volume inside the chest decreases.
  4. The pressure inside the chest increases and air is pushed out of the lungs through the mouth.

How can you increase your lung capacity?

You can increase your vital lung capacity by exercising regularly. A larger vital lung capacity means that more oxygen can enter into the body. Athletes train themselves to have a larger lung capacity than normal. This is to allow as much oxygen as possible to be transported to the cells in the body, increasing their performance.

Where next?

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