There are a few VO2max estimators out there that claim to be able to detect VO2max from a combination of power and heart rate, and they don't require periodic test rides at VO2max. They just watch every ride you do and work their statistical "magic".
I like the idea that you can just ride, because VO2max efforts are not pleasant. But are these estimator algorithms accurate? Are they precise?
Even if the absolute number is not accurate, watching changes over time might be useful. I started tracking VO2max generated by
HRV4Training, increased my riding time in October, and the trend line pointed upwards somewhat:
And while the absolute numbers are nothing to brag about, it's encouraging to see an increase in response to more training. And hooray for not having to do VO2max fitness tests!
For what it's worth, the author of the estimation algorithm
explains it in detail here.