VO2 Max Score

[RunMVW]

My Vo2 Max score increased last month to 48-52, which is great. I had been hovering in the mid 40s so I was glad to see the win. That said, it has stayed as a range instead of settling in on a score. Is that normal or is this just a period of adjustment?

[Heather-S · Accepted solution]

@RunMVW Your fitness score will only show a range of numbers until you do at least a 10 minute run with connected GPS. 

Once you do a run, it’ll update with a solid number. 

For more info, check out this article: https://help.fitbit.com/articles/en_US/Help_article/2096#estimate

[RunMVW]

Ah, that explains it. I took some time off from roads and trails for the elliptical as I recover from a little surgery. Mystery solved! Much appreciated. Run for your life...

[KievT]

If you run on a treadmill, does that diminish the accuracy of the VO2 max estimate?

[t.parker]

@KievT I don't think running on the treadmill contributes to VO2Max. You need to run with GPS and (AFAIK) the elevation must indicate a relatively flat surface for a couple of minutes (usually it's 12 minutes run but Fitbit requires 10). The test is called the "Cooper Test" (I expect this is what Fitbit uses to estimate VO2Max).

[KievT]

I guess I'm curious how the VO2 max estimate of a device that is not always connected to GPS like the Inspire 2 compare to those that have its own GPS (Charge 4, Sense, Versa 3). I can't find any direct comparison online. Thanks for the input!

[t.parker]

This is Fitbit's own thing and probably nobody knows. To be honest, I'm not even sure if they use Cooper Test (just educated guess by reading what the requirements are). Fitbit very rarely reveals what science (and if any) stands behind their scores.

[Wolfpants]

I’ve done 2 runs over 10 minutes this week but my score is still a range. Is there a number of runs required to get a specific cardio fitness score?

[t.parker]

@Wolfpants did you meet requirements like running on flat surface with GPS? I suggest to do 20min max effort under such condition so there's better chance part of your run will satisfy Fitbit's algorithm. For me, I don't know when it changed from range to number. Just in 2022, I completed 281 runs so can't tell if there is a minimum number of runs. If there is, I missed that 😁 (although, I don't think so there's any minimum, a single run executed properly should be able to provide VO2Max).

[Wolfpants]

No I haven’t been using a flat surface. I didn’t know that was required. I’ll give it a try once I find a flat enough area. Thanks