Originally Posted by
JohnJ80
Looks like it would be a glitch in the hardware. Maximum VO2 max heart rate for a 65yo male is 155 and 150 for a 70 y.o. I suppose you might be one in a million, but that's a pretty significant deviation from average.
Heart rate - Wikipedia, the free encyclopedia
J.
That linked chart is the discredited "220-age" formula. Do a bikeforums search in the 50+ forum and you'll see reports way higher, or sometimes lower, than this calculation.
(The newer formula, HRmax = 205.8 − (0.685 × age) happens to be perhaps 2 to 5 beats low for me. But the wikipedia mention of it says it has a 6.4 beat standard deviation. )