HR Concerns - It is inconsistent

FYI: With the latest firmware update Garmin has made it very easy to compare wrist heart rate to external sensor heart rate.

That is because Garmin now keeps the wrist HR sensor always turned on even when an external sensor is connected and the watch writes wrist HR to the activity FIT file. Anyone can open their activity FIT files and compare the values.

I've just realized that Fit File Viewer tool has an ability to graph arbitrary values from the FIT file and compare one value against another. That works perfectly to graph the HR (when external sensor is connected) against the wrist HR. Here is how this looks:

When you use this feature make sure to toggle single y-axis at the bottom so that both graphs have the same scale.

As you can see from my today's run example, for the first 30 minutes wrist HR was lagging behind, sometimes up to 20 bpm lower. Then for some time it was stuck higher above - up to 20-30 bpm higher. Then it was sort of in sync with the external sensor but lacked any sharp changes in HR. This was a trail run on variable moderately hilly terrain, so all those changes in the HR from the external sensor are real.

As I said above, anyone who has an external HR sensor can now easily reproduce my experiment - all you need to do is export the FIT file from Garmin Connect and upload it (anonymously) to Fit File Viewer tool. Then click at the "Chart" icon at the top.

Wow, Garmin are really doing some aggressive smoothing with the OHR these days, likely in an attempt to discard anomalous readings from cadence lock and general "noise" from the watch moving around if it's not strapped firmly. It's probably fine for steady state runs, but I'm definitely sticking with my strap for anything more vigorous. Thanks for presenting that data.

My old Fenix 5+ was both less and more accurate in different ways. Less accurate because it would shoot to 180 and cadence lock the moment the weather became cold or I became too sweaty, but it was dead accurate for the other 95% of the time, responding instantly to increases and decreases in heart rate (correlated with external monitors I'd wear from time to time). The Fenix 7 seems to be more accurate on average as it doesn't seem to cadence lock any more. The heart rate is normally within a 10 bpm ballpark of where it probably should be in my specific case, but it seems to come at the cost of not being able to respond to rapid increases in HR where the watch now wants to discard the first 20 seconds before it decides that rapid increase isn't actually an anomaly.

OHR is fine for hikes and sedentary office stuff, but the strap is a bit of a no-brainer for any real training as you get the super snappy response and all with zero cadence lock and no algorithmic smoothing.

How many athletes use garmin pay while exercising? I tried to use it but none of my cards are supported. 

I wear the watch daily and my normal watch. So when I’m on the trainer with chest strap, I don’t take my watch off. However, while on the trainer and HR is 170 bpm using chest strap and my watch says 80 bpm, that’s stupid. Whether I have the watch running an activity or not, it should display current heart rate. I bought an apple ultra 2 watch because I was pissed at the Fenix 7. The ultra picked up heart rate equally as well as my chest strap while on a trainer ride. No activity started on the ultra, just reading heart rate. I have a friend who also has the Fenix 7 sapphire solar and he has the same exact problem. Didn’t have the problem with Fenix 6 sapphire. It’s definitely something with the watch itself. Hope that clarifies your question of why I’d have my watch on while on the trainer. 

Pierrotsc said:

How many athletes use garmin pay while exercising? I tried to use it but none of my cards are supported.

You've never grabbed a coffee or a Gatorade after a run/ride? How annoying would it be to have to key in your pin again after every activity.

Bought an apple ultra 2 because I was pissed the Fenix 7 was crap for heart rate. First trainer session with the ultra 2, heart rate was tracked perfectly, even without “starting” an activity. It recorded all the way up to my session max of 184 bpm. Fenix 7 would get to around 120 then drop to 85 and not change. It’s a Fenix 7 sapphire solar issue. Clearly. I have a friend with the exact same watch, same issue. Neither of us had this issue with Fenix 6. Also, my HRV has gone from daily average of 38 with Fenix 7 to 59 with apple ultra 2. I’m fit af for 53 and I expect a $1000 watch to perform as it should. Like I said, the Fenix 6 was great. I have an edge 1040 solar and it’s awesome. Figured the solar on the watch would also be awesome. Wish I kept my 6 instead of wasting money on the 7. 

Dfdelong said:

However, while on the trainer and HR is 170 bpm using chest strap and my watch says 80 bpm, that’s stupid.

You're missing a key bit of information here because if you'd started an activity, your watch would connect to the strap and show you the HR pulled from it.

You should clarify and say you've jumped on a static trainer without starting an activity, hence your watch is pulling HR whilst in a "low resolution" mode - the kind it activates when it thinks you're being sedentary in order to save battery. Youre not moving your wrist, hence it hasn't detected activity and switched over to it's "high resolution" mode which is why it's under counting.

Hope that clarifies why your watch is under counting. Start an activity next time and you'll get accurate metrics.

The rides I did had the Gatorade included at each stop :) but I see your point. I could pay at the gym while having my strap. I still have a 6 pro and that is not an option as the wohr is disabled while using a strap.