If you keep the optical heart rate on while wearing the watch overnight, the RHR will be unusually high (up to 80s) despite subsequent readings in the 40s. This needs to be fixed.
Same for me. Even though there are clearly lower readings before going to bed (~mid 40s), a much higher value is reported in the daily history afterwards (~mid 50s to low 60s).
If I turn off the watch while I sleep, no such effect occurs.
Not a master here - I think what you're seeing is intentional by Garmin. If there's no sleep data available it uses the lowest reading (minute average I think) from the day (which is what most people consider RHR). If there's sleep data available it uses the average from the whole sleep period (excluding some outliers). This I think causes some confusion but I happen to like the choice. For me my sleeping HR is usually about 5-10 beats higher than my lowest daytime (which is often when I'm in a chair doing paperwork). However I like the fact it's an all-night average and it seems to pick up when I'm overdoing it/unwell etc. Main downside I find is that if I train late in the evening my heart rate stays high for the first few hours of my sleep and affects the reading. ??? I think this is a common enough complaint though that it would be nice if Garmin made it selectable. But I'd keep it the way it is.
In the Garmin a Connect App make your usual sleep time = your wake time. This should fix the issue and prevent the watch/app from overriding your lowest RHR during the day with a sleeping RHR (unless it’s lower of course). Instead it will measure your LOWEST RHR during day or night.
The commonly accepted measure of RHR used by sports scientist and athletes is your ‘waking’ RHR. I would say 6 times out of 10 my lowest RHR is when I am awake, usually at night a few hours before bed. Prior to finding this fix I would get RHR in the 30s during the day that would be overwritten by higher measures when I was sleeping which was really frustrating! Luckily it works fine now - let’s hope Garmin don’t change it again.
Interesting fix - does it muck up sleep detection? (not that mine is great; it usually decides reading in bed or watching TV before going up is part of sleep).
I have brought this up before to the dev team, and asked for a simple setting to only calculate RHR during waking hours. I've been told that it's being "considered".
BenBristol, do you have sleep and wake times as the same?
