18.23 automatic detection max hart rate

olosip said:

Maybe it uses a calculation unknown to me?

There is no calculation here - just measurement and  detection.

AUTOMATIC MAXIMUM HEART RATE DETECTION

If a heart rate higher than your currently set maximum is identified and passes a reliability threshold, your personal maximum heart rate is updated on the device or in the Garmin Connect app.

no, this description is not good in this form. the auto max hr detection is a firstbeat feature which try to predict your maximalHR from a submaximal effort (depending on HRV and probably on other variables). so this is the reason why you get a new maxHR value even if your highest HR value was far below during an activity. (and the algorhithm can decrease this value also, depending on the actual body state) this feature was told by many times by Garmin staff....  (fyi: it is a new feature since 955, in the previous Garmin models it was working as the description says, just measure the hr and the highest hr value will be your maxHr value)

This is the first time I have heard this explanation, I was not aware of it. Could you please put a link from firstbeat here where they describe this? Anyway, there's a thread on this forum where a Garmin moderator, asks users to report when their devices record max hr even when not recorded, if I find it, I'll post it here. Bye and have a nice day, I look forward to hearing how the discussion evolves.

Here is the post: forums.garmin.com/.../max-heart-rate-changed-without-meeting-the-new-max- heart-rate-during-the-activity

the Garmin never inform the "simple users" about the "how does it work" or "what is the criteria for x or y". It is industrial secret. Especially in this forum they dont write infos to the publicity. Sometimes they ask things but never reply :)