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why does no one care about the totally wrong optical HR-measurments?

I dont get it. Am I the only one seeing the wrong measurements of the optical HR-sensors of all watches?

Simply shake your hand for a while and ask yourself, might this reported heart-frequency be accurate?

Or do something like pushups (where your actual HR rises very fast but your wrist doesnt move that much)... isnt the reported heart-rate way too low?

The only situation where the watches report a near accurate measurement is during very smooth runs / walks. If one has another fitness-watch available or some other form of HR-measurment (like Chest-strap), the deviation will be visible, and can be up to 200%, depending on the activity. 

this "feature" is intentional, but there is no logical reason, why the devs of garmin shall couple the arm-movement to the heart-rate measurement. Or is there?

btw: I have tested every single model on the market currently available and for some of them I've tested multiple devices, just to be shure. 

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  • Just my two cents if you are truly a subject matter expert then you are wasting your time preaching and patronising others here who mostly have no idea what you are talking about. You should take this matter to Garmin and other makers developing OHR technology.

    I think sometimes people stress themselves so much with data and battery life on their device they forget to get outside do some exercise and have fun.

  • "A picture is worth a thousand words."

    You specifically mention the Forerunner series, so I thought I would chime in with some actual data, instead of a lot of empty words.

    OHR (blue) vs chest strap (orange). Strength training (Upper back, Biceps, Chest). A lot of wrist flexion throughout the workout.  Variation? Yes. But OHR tracks well enough.

    (FYI - I use the Auxiliary Heart Rate data field to capture the chest strap, and it is logged along with the OHR in the .ffit file.)


    I can produce many more graphs like this to show the accuracy of my FR945 is versus the chest strap I always wear.

    What matters, in the end, is burning calories. There's less than 100 kC difference between the two graphs.

  • I have Experienced this bad accuracy on FR35 during Weight Training, Wearing watch on ankle does help. Most people don't care about such things as long as you can post to Strava. Sometimes when walking with heart rate @ 90 it will jump to +- 140 and then quickly down again. It's a cheap watch so I think this is normal. (Or Not ?) I wear my watch 1 inch from the wrist bone. The Strap isTight enough.

  • ok, than the interesting question is: will this chart change when you just use the OHR without strap and do the same exercises?

    If not, than it would be very interesting, why your watch has a completly different sensor-firmware than all the models I have access to. And why Garmin refuses to do anything about this issue.

    BUT: looking at this graph, this is highly unlikely to come from actual strength training, as your HR is way to low in the peaks. If youre really doing strength (and going to your limits), your HR will rise to 160-180 and then go down to like 120. This looks more like a fast-paced walk through the park. 

    The easiest way to tell your actual HR is to press your fingers onto your neck and count the pulses and compare that to the clock

  • This is using the OHR , Walking. I'm concerned about the false peaks.

  • will this chart change when you just use the OHR without strap

    Uh.... Of course the chart will change... There won't be chest strap data..Duh...

    why your watch has a completly different sensor-firmware

    I have zero idea what you're saying. Completely different sensor-firmware? How is that even possible? I have stock FR945 (ver 4.10) firmware.

    this is highly unlikely to come from actual strength training

    Are you calling me a liar? When I say it came from strength training, it came from strength training.

    If youre really doing strength (and going to your limits), your HR will rise to 160-180

    You clearly don't know *** about human physiology. Strength training is not a cardio activity. There is no way in hell that a well trained person will have a heart rate of 160 to 180 bpm during weight training. I've been weight training since I was 16, and I'm 56 now. My "max" HR (calculated) is 164 bpm... And, even when running hard it doesn't get anywhere near 160 bpm - maybe 140 to 150, but 180?????  

    Stick to being a "subject matter expert" in sensor development.

  • obviously you knot *** about human physiology as well. If youre not able to reach youre personal max-HR then your sensor does not work or your really not able to push yourself to your personal limits. Getting to 180 is for me (36) easy, and for all friends I know too. Especially while doing weight lifting everyone I know has an HR in the highest zone for a short period of time (like for 30 seconds or so), this is totally normal as your body needs large amounts of oxygen in a very short amount of time. After that the HR falls rapidly. 

    And if you HR stays in the lower zones, than youre just doing simple exercises to keep your fitness-level, without progression.

    And why the hell are we even discussing that. It is a matter of fact, that at least all European models of all Garmin watches DO NOT WORK. The semi-knowledge of trux and co does not help anyone here.

    But I give up on this point. Its pointless to try to get any real answer. I already have my answers from this thread. Simply no one knows about this issue and no one wants to know, so it is easy to not care as less knowledge means less responsibility.

    So Im staying frustrated about the incompetence of the Garmin-Sensor-Devs and will not be able to do anything about it, but buying another brand and forget about Garmin forever. One year of pain (discovering and proofing my findings) for nothing...

  • Former Member
    0 Former Member over 5 years ago

    My fenix 6 pro saffire does the same thing.

  • Can you be more specific please.

  • This is a bit of an old thread and I don't understand why OP got downvoted so much, but I've been experiencing the same issues on my VA3 and Fenix 6 Pro. I do a lot of incline treadmill where the speed is low, but I still manage to get my HR high as it's incline. And sometimes (not every time) the HR just stays at 90-100, even though my manually checked HR is more in 160 - 180 range. But if i start running for a couple of minutes, the HR starts catching up and then reports correctly even if I slow down later. This has happened with swimming too, where I had to change my way of swimming to involve faster arm movement to get the watch HR to the correct range.

    And when the HR gets stuck in that 90-100 range, nothing works - I tried switching inside/outside of wrist, higher, tighter, more loose, etc. Basically everything that has been suggested. This was more prominent on my VA3 though than the fenix.

    So yeah, for me it also seems that wrist HR is somehow including movement into measurement and calculations.