What happens during normal breathing? | ResMed

What happens during normal breathing?

To understand what could be affecting your ability to breathe properly, it’s helpful to know what normal breathing looks like.

The upper and lower airways

It might sound simple, but it’s important to realise that breathing is not something we have to consciously remember to do. It’s a reflex that is controlled by nerve cells in the brain and spine. The respiratory system is made up of 2 parts: the upper and lower airways. The lower airway is protected by the chest cavity, which also contains the heart and lungs.


Upper airway


Lower airway

The breathing process


What starts the breathing process is actually the effort you make to draw air into your body.

When you breathe, the air entering your nose is cleaned, warmed and moistened. It then flows through your trachea, your bronchi and down to the alveoli of your lungs.

As you inhale and exhale, your chest and ribs expand and contract to allow for the air going in and out.

Abnormal breathing

As you can imagine, the everyday act of breathing can become very difficult if you have a respiratory condition that affects the airways, muscles, nerves, reflexes or organs involved in breathing.

How to treat COPD and other respiratory diseases?

Learn how non-invasive ventilation (NIV) or invasive ventilation (IV) could help you to breathe more easily.

Learn more about chronic obstructive pulmonary disease (COPD): its causes, stages, diagnosis and treatment.

Learn about respiratory diseases such as COPD, OHS, neuromuscular and restrictive lung diseases and invasive or non-invasive ventilation treatments at home or in the hospital.