Thanks for the information. Our HR zones are based on lacate threshold HR, not HRmax. HRmax is not a valid basis for determining intensity zones because it does not change as fitness changes, whereas LTHR does. In any case, the best way to get zones that align is to determine your power zones through testing, as you’ve done, then do a ride at your FTP and not the HR that aligns with it. Use this number as your LTHR and calculate your HR zones from it.