Why do I keep seeing people use 6 minute TT pace used for VO2 max?

pocoloco wrote:

Yes, it is obvious that you train to Race. You train to race FAST. I think there is a good consensus that training your metabolic systems are more important than training at race pace. Of course you will get adaptations either way, but we are looking to train OPTIMALLY. Why else would elite marathon runners do VO2 workouts or Threshold workouts, when there race is run slightly under their threshold pace? Lydiard was certainly a revolutionary coach, but he never had runners doing 26 minute 10ks either. His program was not perfect by any means.

That don't make no sense.

darkness wrote:

JK had probably the best explanation I have ever read about VO2 max repeats. I understood it before but his explanation was very plain and common sense.

It has been years since I have read it but I think it is still on this site, and all of you who can't figure out on their own that a 6' Time Trial is the wrong way to go about it should read it.

Here you go:

He advocates 10 minute race pace.

The primary reason you see the 6 min effort cited as the pace for VO2max is because, for an effort the lasts longer than 10 min, the individual will likely not achieve VO2max. If one picks an arbitrary distance (e.g. 5 km), some less elite runners will take > 15 min to complete that effort, and they will likely not reach 100% VO2max, and if so, just near the end. Even most elites, won't spend much if any time at VO2max if running at 5 km pace. If you perform intervals at that pace for much shorter periods, they won't be at VO2max. So, if you're training at 5 km pace, you're training at 5 km pace, but likely not at VO2max.

Why 6 min? It's long enough to allow time for VO2 to evolve to max (requires at least 90 sec), but not so long that you don't get there. BUT, depending on how you test for vVO2max (e.g. Billat's approach or someone elses), it could be 4, 5, 6, even 8 min (tlim @ vVO2max). 6 min is in the sweet spot where you know you got to VO2max, but not so long that the intensity is too low.

The OP refers back to texts such as JD and Pfitz/Coe, who use the 5 km pace, or similarly lenghty efforts to determine VO2max training pace, and this likely comes from the view that the best way to train VO2max is to train slightly under it, as to not incur too much strain. Whether this is the correct approach or not, we will likely never know for certain.

Steve

A personal study on tlim of VO2 max:

In 1989, as a graduat student (grad. assistant) in exercise science, I was in the human performance lab every day testing people. One day, it was slow and I asked the techical lab director if he would do a VO2 max test on me.

After the test, Jeff and I looked at the printout of O2 and CO2 conumsed and produced during the test. We weren't 100% sure which stage I had reached VO2 max. Two stages in a row appeared to have the same amount.

I went home later that afternoon and looked over the printout carefully. I decided to go back and run at an average of the highest two stages on the treadmill (without gas analysis - just run at that speed and grade as long as I could). After a progressive warm up, I ran 7 minutes and 12 seconds at that workload before stepping off the belt in exhaustion. I was totally spent!

The following spring or late winter I had Jeff test me again. My VO2 max was higher by 3 mls/kg/min. and it was clear in which stage I reached VO2 max. So, I did not have to average the two when doing my tlim (personal) study. Three days later, I ran on the treadmill without equipment attached to my head and mouth. I ran 6 minutes 48 seconds before stepping off.

I actually fell to the ground and lie in a heap for a few minutes before being able to walk well; which turned out to be a problem with the lab director who chewed me out for getting his floor all wet from sweat. I remember thinking: when's the last time your out of shape (fill in word)ran so hard you couldn't stand?

Why didn't you just override your CGM and run for 10 min? ;)

Steve

1: Med Sci Sports Exerc. 2000 Feb;32(2):464-70.

Determination of the velocity associated with VO2max.

Nothing like a good central governor joke, Steve.

I got a million of em. Nah, seriously, just a bit nostalgic for the Noakes debate Tinman was involved in a while back.

Steve

Steve McGregor wrote:

Why didn't you just override your CGM and run for 10 min? ;)

Steve

Orange juice just shot through my nose onto my screen!

:-)

Steve