Elevation differences - power & pace

I live here in Colorado, but I have a triathlon coming up at sea level. Any good guidelines on how much my power would change going to sea level? My understanding is that my overall power should go up, but top-end (VO2) may not change much as the higher intensities are more challenging to train at here at altitude. But given that I’m doing a 1/2 iron distance, I have no plans to approach VO2 intensity at any point. I’m really just looking for a feel on how to adjust my pacing for the race. For example, say I was planning on averaging 200w for 2+ hours in a race in Colorado, would that go up by 1%, 5%, 10% by being at sea level?

And similar question for running. I’ve seen people say “your running pace will increase 10-20 seconds per mile” when going to sea level. This question is a little less important, as I typically “just hang on” for the run.


Great question! I wrote a training tip on this very subject, though reversed!


Check it out! Going from 5000ft to sea level you should see an increase up to 5% in power, especially at a more aerobic pace, one that’s under threshold, with that duration and running after.

The other benefit of racing at sea level you may experience is your ability to recover! More oxygen to work with allowing the muscles to recover easier.