The highest HR measured by my Edge 1030 Plus is 180 bpm, and so that became my max HR. However, since updating to version 3.0 of the software with auto update enabled, after a session, if my HR topped out in the 170s, it says new max heart rate detected and replaces the 180 with the lower 170s value. If I notice this message, I then have to manually set the max HR back to 180.
However, I don't always notice that it has done it, so it's particularly annoying when days later, I do find out and subsequently discover that all my zones and stats that are based on max HR have been wrong for all the intervening sessions. As a result, I have now disabled the auto update feature.
Has anyone else noticed this?
Update:
It's been a week now since I disabled the auto update feature, but I just checked the max heart rate setting and found it was back to 171, despite the setting still being set to off.
My max heart rates for my last week's activities were 145, 173, 161 and 141 bpm.
The device auto uploads / downloads data via wifi, so I don't know if it's picked up the old (wrong) 171 during one of those times. I've just check the Garmin Connect on the web and the max heart rate was indeed set at 171 there. I've now updated that to 180 bpm as well.
I'll keep checking both figures and will post back if either of them changes.
Update 2:
Having previously set both the device and web's max HR to 180, I've just done a work out and immediately afterwards, both the device and the web were back down to 171 bpm, still with auto update off! :o(
Update 3:
I think I've discovered the cause / bug.
1. Check the max HR is set to the correct value. ('My Stats / Training Zones / Heart Rate Zones / Maximum')
2. Change your weight. ('My Stats / User Profile / Weight')
3. Check the max HR again and it has now changed to what appears to be a value equal to (220 - your age).
Update 4:
Further experimentation has shown that changing any one of Birth Year, Height or Weight (but not Gender), will set the Max HR to (220 - your age), irrespective of whether Auto Detect Max is on or off. This explains why initially, when Auto Detect Max was set to on, it was detecting a session's max HR in the 170s as being a new max HR, because unbeknownst to me, it had already lowered the stored max HR to (220 - my age).
