What is AVO2 difference?

The AVO2 difference refers to the difference in oxygen content between arterial blood and venous blood. This metric shows how much oxygen your muscles extract from the blood during exercise. In simple terms, it measures the amount of oxygen your tissues use.

For instance, if your arterial blood enters a muscle with 20 units of oxygen, and after the muscle has extracted the oxygen it needs, the returning venous blood contains 5 units, the AVO2 difference would be 15 units. The larger the AVO2 difference, the more effectively the body extracts and uses oxygen, which indicates better cardiovascular fitness and a higher VO2 max 1.