Heart rate too low during run, then jumps up.

When running with my watch it shows heart rates thats way too low. I set one of my best times on my usual running route, yet my watch showed an average heart rate of 132 - my apple watched had me at an average of 160 to 170 on the same route Towards the end of the run it shot up very quickly. The chart below shows my heart rate for my run.

Afterwards i tried going for a run again and experienced the same thing, chart below:

Has anyone had similar experiences? Should i return the watch or is it possibly a seeting i got wrong?

0 bfinary 9 months ago

You're probably not wearing an HR strap. Garmin's are useless without one. All of them

0 5236371 9 months ago in reply to bfinary

Nope im not, i was expecting one of the most expensive smart watches to atleast be able to accurately measure heart rate without any extras

0 bfinary 9 months ago in reply to 5236371

Optical HR are generally poor. Garmins are especially so

0 5236371 9 months ago in reply to bfinary

But this is out with 40%, might as well guess you heart rate without any watch

0 entify 9 months ago in reply to bfinary

Bad day? Cause thats a bullshitty thing to say and a lie.... It may not be great for you, but your experience isnt the conclusion for everyone, sorry to disappoint you.

Ive never had a watch hat matched a chest strap as accurate as the Fenix 8. Its literally spot on me 99% of the time and when its off its only by 1-3 bpm..thats not useless is it? Base, interval, tempo it dosent matter its as accurate as the chest strap on me for running..the only activity where the sensor performs poor on me is weight lifting. Accuracy is highly individual so dont come here saying its useless. I can provide data screenshots if anyone wants to see how great this watch can be

0 5236371 9 months ago in reply to entify

Based on what youre saying, im thinking there might be something wrong with my sensor? Or does the watch need time to calibrate to my heart rate or something?

0 bfinary 9 months ago in reply to entify

Watch the scientific reviews. Garmins are always poor. My Epix was poor and the F8 has the same sensor and is also poor. They are reasonable in warm conditions. Very poor in cold conditions.

If I’m racing and want to train around threshold I need accuracy. Garmin’s OHR doesn’t cut it. I’m ok with that, hence I bought an F8 and continue using the strap.

0 davesparx 5 months ago

I have this on every run as well at around 10 minutes

0 davesparx 5 months ago

Mine does this every time at around 10 minutes

0 simacekjakub 5 months ago in reply to bfinary

I have never had any issue with optical sensor during steady runnings. I wear HRM-Pro+, so I can compare those measurements and I can say that all of my runs have nearly the same heart rate from optical sensor and from strap, I can see it in the graphs. There are max 1 to 2 percent differencies, never occured drops like this.

During inline skating it's also quite good. That's not always the case when cycling, but there is a lot of wrist movements, so understandable.

It also depends on how snug watches are worn, skin color, tattoos, hair color and density...

But yeah, there is more people having this issue.