DVCFan1994
DIS Veteran
- Joined
- Jan 30, 2013
- Messages
- 1,469
I definitely takes a few weeks to really zero in, and it isn't as precise as a manual calculation, but it is very helpful for establishing a baseline and tracking improvement. I certainly don't swear by the actual VO2 calculation, but I still use it.
As for the training effect - after a few weeks this is very helpful. Most runs should be right at 3. If you are consistently at or near 4 in training effect, you are running too hard and not getting maximum benefit from your running.
I've never done a lab based VO2max but from what I've read the value the Garmin outputs and the lab based test are close (within a few points) when using the HR strap (so a good estimate but not a replacement). The Garmin calculates the VO2max based on HRV (heart rate variability) when you use a heart rate strap. But the Garmin 235 can generate a VO2max with only the optical HR monitor through a few data manipulations in their formula. You'll need to run with it a few times before the data becomes more accurate because it needs more HR vs pace data points to figure out a curve for you. Entering an accurate max HR and resting HR does play a role in the VO2max and training effect output so make sure those are accurate as well.
Lastly, the estimated race pace that it spits out is a best case scenario. It assumes you have maximized all of your abilities to hit that number. So when your PRs are minutes or hours away from those times, don't worry it is for almost all of us. What the race predictor does say is if your heart rate was the only variable in running then you would be capable of that predicted race time. As an example, most people finish a marathon at between 60-70% VO2max. The Garmin's marathon estimated finish time is based on a 77-85% VO2max finish (the higher the VO2max the higher on the % curve it puts you and the more unreasonable it gets, though there is probably a connection between someone with a higher VO2max being able to run at a higher % as well). Physically it's possible, but almost none of us will be able to reach that predicted race time.
Thanks to both of you! My VO2 was better than I would have expected, sort of in the too good to be true category. And my training effect was 4, but today was a purposefully harder effort than usual. It will be interesting to see how things change as the more data is available. My max HR (195) was from a recent test, and having worn a Holter monitor for a whole month last fall I have a solid understanding of my RHR (~50 as long as I'm not sick).
And the predicted race times? All I could do was laugh at them. So clearly, the watch has some math to redo
