Heart rate not accurate

Former Member
Former Member

SOLVED: the watch was not tight enough. Has been accurate since.

I received my 6X Pro yesterday; my first Garmin. Sitting around my house yesterday, the wrist HR reading seemed accurate. I did a stairmaster workout today and was surprised to find that my HR would not go above about 80. This was obviously wildly inaccurate as my HR was actually fluctuating between 150 and 170. A few minutes after getting off the machine, the 6x started reading a HR around 110 as I was cooling down. 

I did a few quick tests on a stationary bike with a chest strap and found that with a HR around 130to 135, the 6x wrist HR was reading between 100-110.

I understand a optical wrist HR sensor is not going to be as accurate as a chest sensor, but this is so far off that it is useless.

I am going to try a few adjustments over the next couple of days, such as how tight I make it, how far up by wrist I place it, and trying it on the underside of my wrist. If those don't work and I can't find a solution, I feel like I'm going to have to return this. I really want to figure this out because I love everything else about this watch. Any advice?

  • For a lack of a better analogy, that's like wanting to count calories for the food you eat for breakfast, lunch and dinner, but not for any snacks in between because they're not real meals.

    I think we’re getting there.. Thanks for the analogy. I would really like the snacks to count towards the calories, but as it is only the meals are counted and the snacks are counted as if I’m drinking water. 24/7 measuring has to be just that, regardless of starting an activity or not. But I’ve really had enough. I’ll keep the F6 pro for activity tracking, but for 24/7 tracking I’ll switch to a Fitbit Charge 4. If 24/7 tracking is fixed on the F6 maybe I’ll switch back, but I’m through waiting for fixes that probably will never come. And the stale Garmin ecosystem is boring me too, but that’s an entirely different topic.

  • I honestly understand Jeremy.  You shouldn't have to start an activity to get a correct HR.  I don't know why this isn't a problem for some and a nightmare for others.  I know if it was an issue for me, I'd be upset too.  I was just confused about you saying you're starting an activity (an unnecessary work around you shouldn't have to do) to get the correct HR and then deleting the activity so you're metrics weren't messed up.  My view is an activity is an activity, therefore I would want the metrics for each and not just the HR for one as this would affect training status, 7 day load, 4 wk load focus, and recovery time.   Anyway, keep your hopes up on a fix and stay safe.  I'm not sure how this virus is affecting your area, but the state of Washington just extended their current two week stay at home order another month.  My cycling, runs and hikes are now cardio workouts in the garage and I'm starting to go stir crazy.  Stuck out tongue winking eye

  • Former Member
    0 Former Member over 5 years ago in reply to tess

    Roger that

  • Thank you and stay safe yourself! I’m from the Netherlands and we’re not in a complete lockdown, but are allowed to go outside to run or cycle (or go to work or do shopping). There are much bigger problems in the world than inaccurate WHR.

  • Hi Garmin Team,

    i bought the fenix 6x pro solar (Currently installed Software: 8.1) a couple of months ago thinking that a watch in this price category might be able to track key statistics pretty accurate. However as I started indoor rowing, i had some suspect heart rate readings (ok indoor rowing has a lot of wrist movement). However I had similar problems when doing other activities and so I bought a HRM Tri Strap to check the WHR. I started practicing yoga as i cannot go to the gym right now (closed due to corona) and tracked the difference between the WHR and the Heart rate reported from the strap. I further occassionally checked the Heart rate readings manually and using a finger pulsoximeter. The strap readings, pulsoximeter and my manual readings matched pretty well.

    However, the WHR reported from the watch wasn't even close to the actual readings.

    Just to be clear, I started the activity, did some warmup. It was not cold in my room, i cleaned the sensor and I even shaved my wrist. I did pretty much all you mention in the above links. I don't even have tattoos. I tried to move the watch and tighten the watch.

    I attached a comparison of the different readings over the course of a 90 minute yoga session.

    This is not a single session problem, over the course of more than 10 sessions, i always get a similar picture, so I have more charts if you want to do further analysis

    The correlation between the WHR of the watch and the Strap is just 9.8%, the average Delta is -38 bpm going down to ~-100 bpm sometimes.

    For a watch costing more than 1200$, this is more than disappointing.

    So overall right now I am more than disappointed with the watch. For me, the watch just generates random numbers and I am better off just guessing my heartrate.

    Please fix the WHR.

    Edit: Just to clarify: I really think that the fenix 6 is an excellent smartwatch and I really love it. But as much as I love this watch, I hate inaccurate and biased data. So Garmin, please do fix the WHR problem.

  • Have a look at the number 1 top reply here :  

    with currently +21 approvals, I don't think the problem is small

    forums.garmin.com/.../1014420


    i published one of my tests 2 month ago at the hr tread, linked at the 6.10 FW Thread.

  • For a watch costing more than 1200$, that is more than disappointing.

    It doesn't matter how much money is thrown at this issue, it's simply a limitation of the optical heart rate technology right now; there are some activity types (Yoga would definitely be one) where optical heart rate, taken from anywhere on the arm, just doesn't work very well.  My first optical HRM was a Scosche Rhythm+ strap, that has the market Leading Valencell sensor in.  Whilst that works great for running and cycling (especially worn further up the arm) its HR values are a complete work of fiction whenever I do rowing, circuit training or strength training.  So I have not been surprised that every Garmin watch with WHR I have owned (Fenix 5, Fenix 5+, MARQ and Feni 6X) have similar limitations in such activities.  It's not just Garmin that would suggest you use a chest strap in some scenarios, Suunto https://www.suunto.com/Content-pages/what-should-you-know-about-wrist-heart-rate2/ and Polar https://support.polar.com/uk-en/support/the_what_and_how_of_polars_wrist_based_heart_rate_measurement recommend using chest straps for those kinds of activities too.

    Where I think it is fair to scrutinise the manufacturers for their WHR accuracy, is during normal running and road cycling (or indoor variants of those), as well as 'reasonable' accuracy tracking 'all day' 24/7 HR (and the associated metrics like resting HR, all day stress, body battery and the like).  The manufacturers do directly advertise the WHR on their watches working for these scenarios.

    I think I'm right in summarising that Allalin72 and others, have specifically observed that the HR tracking whilst not in an activity (so whilst in normal watch mode 24/7 HR monitoring) seems to be not so great of late (compared with other Garmin WHR watches).  There does seem to be something in those complaints, but I suspect Garmin are not finding it easy to refine the software to everyone's satisfaction, as the issues don't impact everyone and it falls in to an area where manufacturers are trading battery life against 24/7 WHR accuracy.  That said, it is 100% worth constructively reporting observations when accuracy is not great; in my experience, the Garmin Odsweng folks at the end of the beta email address are genuinely interested in learning from experience and improving where practical to do so.  That doesn't always mean the most obvious and important issues get fixed first (a frequent complaint type seen on these forums is 'why did the Dog Tracking widget thingy get fixed in this latest beta, but WHR is still off in my use case').  Simple binary bugs will get fixed quickly, even if they're not that important (relatively), but complex issues will take longer, even if they are important and impact many people, and it seems optical heart rate accuracy is very complex (just go look at the Valencell website and they make a big thing of how clever their algorithms are to get the accuracy they do).

    In summary, be constructively demanding as customers and keep reporting issues (via the Odsweng beta route or Garmin Customer Services), but also keep calm, be patient and be realistic with the limitations of OHR technology.

  • Unlikely to be fixed. It seems that this is a persistent issue since the introduction of this watch and no meaningful action has been taken by the company. As I wrote a couple of days ago, I never had such a problem with Fitbit, Garmin is really rubbish. Top watch and can’t measure the WHR accurately 

    I am walking 15k per day and it fails to capture anything near real HR. 

    I will write again to the company but they seem to be ignoring the problem. In my opinion the sensor is faulty, it is hardware and not software issue 

  • I get your point and i totally agree with you. To be honest, despite the problem with the WHR, the fenix 6 is quite an excellent smartwatch. But all metrics are somehow based on the WHR and its not just the yoga activity which is way off. That was just one example. As it has been mentioned multiple times here, the 'all day' WHR without starting an activity shows similar patterns once the actual heart rate rises above 100 bpm. I am definitely not expecting 100% accuracy. Especially with a lot of arm movements i can imagine that it is hard to generate accurate results.

    But i mean, the watch isn't the cheapest and for 'all day' WHR, even my galaxy watch has been better.

  • Former Member
    0 Former Member over 5 years ago
    Since the last update the precision of the WHR has been laughable. + - 20 over actual pulsations. Is incredible. It measures worse than a $ 50 watch