Wrist heart rate monitor WHR inaccurate

I'm really wondering if (a) my sensor is faulty (b) no one else is looking at HR much (c) people don't have a feel for what their HR should be in certain daily activities...

Here are just two examples of close to double the expect HR during (almost) complete rest: 

Stable 90-95bpm 10 minutes into a lunch:

90-105bpm after 30 minutes of couch potatoing:

Your "B" and "C" questions are biased. You're assuming that everyone should be having the same issue as you and the rest of us are oblivious to what's happening. You very well may have "A" going on, but let me add the possibility of "D", that most don't have the issue, or "E", the 945 just doesn't work well with you personally, such as fit, sensor placement, etc...   From the photos, the watch appears to be a little large for your wrist. I recall in the past you had an issue with pace on your 645?  Did HR work better for you on that watch? 

I'm not assuming that at all - that's why they were questions. I'm trying to understand if other people look at their WHR and it always makes sense to them. Your "D" (other people don't experience this issue) could also mean my (a) or your "E".

Yes, the watch is slightly large for my watch but like I said, I wear the watch quite tight and the sensor has only a ~1.5cm diameter so I highly doubt that has any effect.

Yes, lap pace on the 645M under tree cover was completely "ruined" IMO versus the 630 and I checked 4 different units. I didn't check lap pace much with the 945 since I now use Stryd for pace and distance (it's amazingly consistent) but the little I checked with the 945 didn't show much improvement over the 645M.

The 645M WHR however gave me a much more plausible HR most of the time.

I too use the Stryd. Great device. Anyway, I asked about the 645 because prior to getting my 935 a couple of years back, I really wanted maps and tried a Fenix.  HR for me was terrible on the Fenix. I'm kind of a data junkie, so I picked the 935 sensor over the Fenix maps. (no worries now that I have a 945).  In fact, the VA3 gave me the best HR results, but that device lacked the features I wanted and only lasted 3 months. My point is, if your 945 isn't defective, you may have to pick the lesser of two evils when picking which watch to use .  As a side note, it's possible to wear the watch too tight.  Those are some pretty good indentations in your wrist. 

I'm also a data junkie :) That's the reason I gave up with lap pace and distance on the 645M and went for Stryd. I might have worn the 945 a bit too tight and though the next notch makes it a bit too loose in my opinion, I'll try it and see if that makes any difference.

Were you experiencing the same HR issues with the Fenix as I am with the 945? (almost) Totally useless HR in large parts of normal everyday life? 

My personal recommendation would be to wear your 945 at least one notch down, if not more. The amount of pressure it would take to leave that kind of imprint from your charging port is likely to affect the capillaries under your skin, and this is where this device will measure HR. 

Hi Former Member, thanks for the post. I have taken your advice into account and have worn my watch one notch down in the last two days - it was definitely too tight. However, I don't see any change in WHR reported by the unit. Is there anything else that could affect it?

As I mentioned before, my previous 645M did a much more accurate job of WHR reading in everyday life. In-fact, I forgot my HR Strap here and there and was very pleasantly surprised from the WHR reading during the run as well.

I thought the HR provided on the watch face wasn't supposed to be real time for battery reasons. You are supposed to go to the heart rate widget if you want the current sensor reading.

I agree it's not real time but it seems to update about every 2-3 seconds so I'm not sure how big a game changer that would be. Having said that, I've also monitored the HR widget and saw the same results.

Next time I can take images of the HR widget, or better, I can take a 1 minute video clip while laying down on the sofa with a constant HR of 105-113 as I saw yesterday for probably about 4-5 minutes.