We're running with my son for almost a year. He's young, so the 220-age would give him a max HR over 200, but since he had the FR245 I set it to auto adjust the HR zones according to the HR reserve. Until today this had a max HR of 173.
Today we had a "casual" (at least for me, but longest ever for the kids) bike ride. It was hot, and they were working nice. At the end I saw that his max HR was changed to 198. (this was with the watch's sensor BTW)
My dilemma is this: should I keep the HR zone settings on the "global" setting (1 setting for all activity types) or should I split it and set 173 for running and 198 for cycling, and let the watch do the adjustments for each of them separately from now on?
The cycling is not really important, we hardly do a few rides a month and not as a training, just for weekend fun rides, but if finally he "proved" that his heart is capable of beating 198 bpm then if I keep this max HR for running as well then it would significantly move his zones up, that would IMHO allow him to continue to run many times when currently he stops telling me: "the trainer told me to run only in Z2-Z3"