12-10-2021 07:35 - edited 12-10-2021 07:36
12-10-2021 07:35 - edited 12-10-2021 07:36
The American Heart Association doesn't even use the same formula. I trust the American Heart Association because those are the same numbers my doctor provided me when I shared the nonsense Fitbit was pushing. See for yourself.
https://www.heart.org/en/healthy-living/fitness/fitness-basics/target-heart-rates