Heart Rate Accuracy Issues with Fenix 8

Hey, there are very similar posts on this forum.

I had the same experience as yours during bike activities.

In my opinion there is an issue related to sensor'readings.

Also I do have a garmin pro plus heart rate strap which is very accurate and I used it to compare the HR values exported from the two devices.

The watch has a delay in readings / spikes and maybe this behaviour depends on conditions like temperature and other external factors.

Garmin-Laurie can you help us on this topic please?

The graph corresponds to my run today. My heart rate drops inexplicably after 15 minutes of running, averaging 120 bpm, even though I was maintaining a pace of 4 minutes 30 seconds per kilometer.

This issue with the heart rate sensor also causes an increase in my VO2 max. Since I bought the watch, I’ve gained two points... 

As it sits now the wrist based HR meter on the F8 is utterly useless. For 3 months now it's never read higher than 100bpm. For context im a cyclist that rides rhe indoor trainer in the winter months and have been running a HR strap paired with my Garmin 540 head unit while also wearing the Fenix 8. Switching back and forth between the two my indicated HR on my head unit using my HR strap will be 130bpm steady state  (which from years and years of experience i know to be accurate in that moment) while the Fenix registers 75-80 beats. It's never wavered from this error and I don't even consider it to be a usable device. 

Firmware is uo to date and reset, etc. Relatively hairless lower arm. 

Dear Coureur,

I have the same experience and I think it is also the cause why the race predictions are completely wrong. I am a 57 year old male who cannot run the half marathon below 2 hours anymore, still my VO2max is rated as 54, 'superior'. It also predicts that I could run the half marathon in 1h46, fourteen minutes faster than in reality....
I have been wearing Forerunners and fenix watches for nearly twenty years now, but I've never seen such grave errors in the measurement.

I then raced with both my daughter's iwatch and my fenix 8, and the heart rate was very different indeed...

I'm experiencing the same issue with my Fenix 8. During an indoor cycling session, my heart rate suddenly dropped to 80-90 bpm, even though I was maintaining the same effort level. Normally, my HR in such sessions is around 125-135 bpm. I suspect the issue might be related to the watch's processor. When I first set up the watch, I noticed some lag, almost as if the device lacked enough processing power. You can clearly see the HR drop in the screenshot I attached. Has anyone else experienced this, or found a solution?

Despite the various updates, the heart rate sensor is still faulty. There's a discrepancy of 20 to 30 bpm compared to my actual heart rate. What is Garmin doing about this? Or is it just my watch that's malfunctioning? I'm extremely disappointed with Garmin, especially for such an expensive purchase

it’s not just your watch. It’s a lot of watches

Happening to me too. I notice it while cycling compared to my chest strap. My Epix Pro Gen 2 didn't have this issue. I also don't recall DC Rainmaker's review of the fenix 8 mentioning this happening. Starting to regret selling that Epix.... 

Fenix ​​8 Solar, same path and pace.