MaxVO2 is analogous to your car’s engine’s horse power. By measuring the difference between O2 intake and O2 exhaled and using a method called indirect calorimetry a calculation is made that shows how much power you are developing. Whereas the car engine’s power is measured directly via a dynamometer. And like the car engine you can’t sustain max power for very long. Try holding your foot to the floor on your car and see how long that engine lasts 🙂 likewise we can sustain maxVO2 for just a few minutes before fatigue will cause us to shut down.
In our books and in this article we discuss at some length why maxVO2 is a first wave adaptation and why it will increase rapidly in the young and untrained but often does not change and may even drop among elites despite performance gains. So I will not go into that here.
MaxVO2 and AeT are not related to one another. I have trained and tested an Olympian XC skier with a maxVO2 of 92ml/kg/min but whose AeT was in the basement. As mentioned in the linked article and in our books maxVO2 has a rather poor correlation to endurance performance. How long you can sustain a high percentage of maxVO2 on the other hand has an almost perfect correlation to endurance performance. The ability to sustain that high % of maxVO2 is what we call endurance and it is highly dependent on AeT.