The Oxygen Advantage: The simple, scientifically proven breathing technique that will revolutionise your health and fitness

by Patrick McKeown

Oxygen saturation (SpO2) is the percentage of oxygen-carrying red blood cells (haemoglobin molecules) containing oxygen within the blood. During periods of rest the standard breathing volume for a healthy person is between 4 and 6 litres of air per minute, which results in almost complete oxygen saturation of 95 to 99 per cent. Because oxygen is continually diffusing from the blood into the cells, 100 per cent saturation is not always feasible. An oxygen saturation of 100 per cent would suggest that the bond between red blood cells and oxygen molecules is too strong, reducing the blood cells’ ability to deliver oxygen to muscles, organs and tissues. We need the blood to release oxygen, not hold on to it. The human body actually carries a surplus of oxygen in the blood – 75 per cent is exhaled during rest and as much as 25 per cent is exhaled during physical exercise. Increasing oxygen saturation to 100 per cent has no added benefits.