What is cardiorespiratory endurance?

Cardiorespiratory endurance is a measure of how well your heart, lungs and muscles work together to keep your body active for an extended period of time.

Explanation:

When experts test cardiorespiratory endurance in a laboratory, they measure how well your heart and lungs deliver oxygen to your working muscles so they can work hard during exercise. When your muscles don't get the nutrients they need, the products can build up and cause fatigue.

So how can scientists measure cardiorespiratory resistance? Sometimes they test the air you breathe out during vigorous exercise. By analyzing exhaled air, they can estimate how efficiently their muscles are using oxygen. But this procedure, called a max VO2 test, requires you to be able to work at an extremely vigorous intensity. So the test is not safe for everyone.