- There is not a lot of monitoring going on overnight. It takes a reading every couple of hours at most. But these readings seem pretty steady although not the lowest resting heart rate in a 24 hour period.
- My low resting heart rate takes place in the first hour or two after I wake. In previous versions, it took place an hour before waking until waking. (You can see the stretch to the left of the little alarm clock - my reading around 54 throughout sleep through waking. The resting heart rate low of 42 took place around 10 am.)
- Resting heart rate averages are amazingly steady from week to week.
- The HR reading jumps to 90-100 when I start walking, even if when I take a manual HR read my pulse is still in the 60-70 range. I assume this is a false reading based on my walking cadence which is around 100. (The peaks below are during a half hour treadmill walk at a low speed; you can see it drop down immediately to a low resting rate once the walking stops.)
I have had the same problem on occasion that some other users have had - no HR reading at the start of an activity. I do check to see if the HR reading has started before the activity is begun - if not, I exit out to the main screen and restart the process. I haven't had this issue of late - but according to the forum that Garmin maintains, it is a known issue and they are working on it.
Also: I am having some unusually low resting readings - 39 is common, when a manual read is more like 46. I think Garmin has tweaked the algorithm productively, but still needs to do a little more with resting heart rates, particularly after exercise.
Additional postscript 5/8:
The update has killed vo2max readings on Garmin Connect. This is a known issue on the Garmin 235 forum.