fitness has almost nothing to do with HRMax - it’s pretty much all genetic.
However, the standard deviation of the HRMax formula is 12-13, which means that about 1/3 of the population is more than 12-13 bpm away from the average.
Not sure of my absolute max HR; max HR recorded is 179
[seems to be slowly climbing… or I’m sometimes reaching ‘ever deeper’; when N=1 ‘controls are difficult’]
The HUNT study came up with a better formula “220 - age*.64” (SEE = 10.8bpm, r = 0.60) and noted:
Previously suggested prediction equations underestimated measured HRmax in subjects older than 30 years.
Indeed, my actual HRmax is 13bpm higher than “220 - age” and 7bpm lower than HUNT formula.
However HUNT has a +/- 10.8bpm, so for example someone 50 years old would have a HUNT predicted HRmax of 177bpm - 199bpm. That is a pretty large range to my eyes, and goes to show just how individualized HRmax is for any given person!!
I have noticed my max has gone up the last couple of years. Pushing harder more than likely. Max happens on outdoor rides. Highest indoors has been 170 roughly a week ago