No, it’s whack. Turn off the alert.

Watch estimates my VO2 max at 25. Other estimates put it at 45-46 based on my min/max heart rate, which aligns more with my actual fitness. I don’t record Apple workouts very often though, I often use it as a Peloton HR Monitor.

Try this:

(max heart rate on an all-out, gassed workout / resting heart rate) * 15.3

Disclaimer: Not a doctor nor a watch.