Does VO2 have anything to do with how long you can hold your breath?

What about sheer lung capacity?

What factors into your VO2 rating in terms of your physical attributes?

What factors into your VO2 rating in terms of your training regimen?

As a side question, why do the NASA people do that test where you have to blow into a tube and hold up a ping pong ball? That was a scene from the movie Space Cowboys. It could just be fiction or dramatization I know, but I thought it was interesting.

VO2 has a lot more to do with the efficiency overall of your lungs and circulatory system than sheer lung capacity. Holding your breath is something that you have to train yourself to be good at. With practice (a lot) most people can learn to nearly double how long they can hold it.

I would imagine that the volume of air you can take into your lungs may have some effect on VO2Max, but I don't think size of the lungs is the limiting factor for most people.

V02 is a measure of aerobic capacity. I know guys (runners) with great VO2's that would get their asses kicked in a Cat5 race around here, simpyl because they have no leg muscle to put out any speed / power. Its not as big of a deal as some people think for cycling.

Also, VO2max factors in your weight, which is not a big deal at all for riding on flats. Although it is for climbing and to a lesser degree accelerating.

VO2 max depends almost entirely on cardiac output. If you measure VO2 max at high altitude (ie less air) the athlete will take more breaths but hit the same VO2 max; or very close due to the small amount of extra energy lost to the lung muscles.

Max cardiac output is max HR x stroke volume. Max HR is genetic and will not increase with training. Stroke volume will (think low resting HR). Lactate threshold not VO2 max is the key to real gains.

That test you saw is for lung capacity.

Your VO2 max measures your body's ability to consume oxygen. The greater your VO2 max the greater your potential for excelling in endurance sports.