r/apple • u/misclurking • 55m ago
Apple Health Apple Health VO2 "Average" Ranges are Skewed
I have run 6 half marathons, and while I'm not even in the top-half of race results, I consider each one a huge personal accomplishment.
I like to take a peek at Apple Watch's VO2 max estimate and while the calculation might be reasonable enough, it is compared to a data set with known sampling bias.
Just like a half marathon, my quartile results look lackluster until you consider that 99% of people don't compete. As a result, race results as a comparison aren't useful without knowing the broader context.
I think the same issue is going on with VO2 max data. In the attached Imgur image, my figures are labeled as below average. Further into the data, it seems my age cohort's average is 43 (ml/kg/min), and anything below is therefore below average.
It seems that FRIEND database data for the VO2 comes from those referred to exercise testing, people enrolled in fitness or clinical programs, or those engaged in physical activity (see Google AI). On average, these are physically active people or maybe those undergoing a known issue, leaving out a lot of groups.
Have I misunderstood this, or is this something Apple needs to improve on? Frankly, if there isn't a good data set for them, maybe they shouldn't even include this average to compare with?
Imgur sources: https://imgur.com/a/MJYCqnu