BREATHING

Breathing, like sleep, is a physiologic function that we all perform subconsciously. The average healthy person breathes at a rate of 10-20 times a minute exchanging ~ 1/2 litre of gas with each breath. This allows the body to take in oxygen and excrete carbon dioxide. The body is quite sensitive to changes in the concentrations of these gases in the blood. For example, if you hold your breath for 5-10 seconds you will start to feel uncomfortable and have the urge to breathe. If you were to measure the concentrations of the gases in the blood during this brief breath-hold, you would find only very small changes.

When you exert yourself, your body increases the frequency and depth of breathing to meet the added demands. If you are working close to your maximum capacity, your breathing will remain at a higher level even after you stop in order to restore your body chemistry to normal after the exercise is over.

Breathing exposes your body to a variety of environmental challenges such as pollution, cigarette smoke, and micro-organisms. These exposures can cause disease in the lungs, the airways, and elsewhere in the body. Breathing can also be affected by processes occurring in other parts of the body such as heart disease and disturbances of the immune system.

The purpose of this part of our web site is to educate the public about common breathing problems. Many of these problems are chronic, and the more you know about them, the better you will be able to handle them.