Vo2 max calculation way off

For what it is worth, there is a big change in my readings over last several months...dropping from 56 to 38...with absolutely no change in my workouts or intensity. It started around October. No idea why.

If you can’t find any VO2 max readings in the Health app, that is probably because you have not yet logged the right kind of workouts with your watch. Only two workout types can produce an estimated VO2 max on Apple Watch: Outdoor Walk and Outdoor Run. (However, I believe Hiking also works.)

VO2 max relates to maximal exertion. So you’ll need to log a pretty intensive workout to generate a reading. And you’ll need to sustain it for at least 20 minutes.

MillionYearsOld wrote:

Apple what do you think?

Apple isn't reading here for this sort of question. Also, I'm not sure that Apple has published the particular algorithm that they use (though I could be gone). You can let Apple know what changes you'd like to see in how they do things here:

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