You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Heart rate wildly inaccurate on Apple Watch Ultra

I went out for a run today and my Apple Watch Ultra heart rate was wildly inaccurate. Running at 7:58/mile pace, it recorded an average heart rate of 180 which is complete nonsense. As an experienced runner, my best guess on my average heart rate for that run would be 135. I'm sure someone will probably ask how I know my heart rate wasn't actually 180 (fair enough question after all). I can say with certainty that it definitely wasn't anywhere near 180 because:


  • I could hold an easy conversation during that run.
  • It felt easy
  • I can run faster than that for several miles


This happens often enough that it bugs me, but doesn't happen every run - sometimes the watch heart measurements are pretty much spot on, other times they're just wrong. I wear the watch strap as instructed (not too tight, not too loose). It was neither hot nor cold at 15 celsius so probbaly not related to skin temperature, sweat or dilation of blood vessels.


Does anyone have clarity on why this happens and how it could be resolved? There seems to be so many people on the community reporting similar, but only generic advice about strap tightness, etc. which doesn't seem to solve anyone's actual issue?


It's an expensive watch, and I chose it because it had one of the best all-round accuracies for heart rate, hrv, sleep analysis etc. Any advice gratefully received - feels like I'm wearing a really expensive alarm clock at the moment.


[Re-Titled by Moderator]

Apple Watch Ultra, watchOS 9

Posted on Jul 18, 2023 11:37 AM

Reply
Question marked as Top-ranking reply

Posted on Jun 23, 2024 11:15 AM

I am a desk jobber, and apple watch ultra 1 keeps me showing 126 to 135 BPM while sitting idle, no exercise, not even walking but it shows 100+bpm all the time.


I got worried and checked my ECG, it says Sinus Rhythm which means normal.


then I checked my blood oxygen, it says 97%.


if everything is normal then how the f**k my bpm is going 100+

Similar questions

21 replies
Question marked as Top-ranking reply

Jun 23, 2024 11:15 AM in response to gary9000

I am a desk jobber, and apple watch ultra 1 keeps me showing 126 to 135 BPM while sitting idle, no exercise, not even walking but it shows 100+bpm all the time.


I got worried and checked my ECG, it says Sinus Rhythm which means normal.


then I checked my blood oxygen, it says 97%.


if everything is normal then how the f**k my bpm is going 100+

Jul 24, 2023 3:56 AM in response to Mike_P1

Thanks for providing that article. I've been through all of the points and it made no difference. However, I do have some further insight as to what's going on....


Went out for another run: Purposefully flat apart from the last 0.2 miles to try and get some consistency in readings. Here's a screenshot from the Apple Fitness app.


The readings from about 18:20 onwards seem pretty accurate - about 125 - 130 average rate with a climb to ~140 at the end for the uphill slog. It's the first part of the run where the inaccuracy occurs where the average heart rate should have been about 125 but was reading intermittently and inaccurately high. I notice the same thing on my rowing machine, where it seems to take about 5 mins to latch on to an accurate reading.


Note that the recovery readings look about right, falling from ~140 at the end of the run down to 120 after 2 minutes.


Mar 6, 2024 1:29 PM in response to gary9000

Same for me since the beginning with Series7.

Apple also replaced my watch; no change.

I’ve been contacted by several specialists.

NO SOLUTION!

I suppose also that the root cause might be my iPhone8 (too old?).


My issue is always on the first Km or 5 minutes; then it becomes regular.


I’m planning to go back to Garmin. with 100€ I have never had an issue on the accuracy.


Apr 4, 2024 1:46 PM in response to gary9000

I am recently experiencing this exact issue. I have not had an issue over the past year and a half, but all of the sudden it is showing a very elevated heart rate when I start my run. I too can sing, talk, etc...which is how I ballpark my exertion level. I do note that my resting heart rate which is usually about 44 is accurate. As Gary mentioned, once to the end of the run, it seems to sort it self out. It sure does mess up zone information though. I am going to try and do a reboot and see if that makes any difference. If anyone has a solution since Gary posted this I would be grateful to know what that might be. My watch is a series 7

Jun 26, 2024 6:01 PM in response to gary9000

I'm with you. i originally bought the apple 6. i was diagnosed for a time with a heart issue and the doctor suggested a wrist monitor would help me keep track of my bpm & resting rate. i am a runner. i run at least 5 miles 6 days a week. the 6 resting heart rate worked flawlessly for 2 years and one day stopped showing me resting heart rate only showing one rate per day. we all know thats just not possible. when i call they try to convince me thats the way it always is/was, just one reading a day. just one average a day. after a five mile run i cant possibly have a resting rate of 52 all day.

SO, i gave the 6 apple watch away to my younger daughter who's only interested in steps, and bought a new watch, the 8. the 8 worked perfectly showing resting heart rate more or less accurately until a week ago and now does the same thing as the 6 did. just showing an "average". when i call apple they give some sort of nonsense about the average, smh. thats not true. it showed me a variable resting rate for 1 year and 4 months. and now, NOT.


[Edited by Moderator]

Aug 6, 2024 11:11 AM in response to apple8watchuser

If I open the Health App/Browse/ Heart -> Resting Heart rate, then choose the daily view, my heart rate show as "Average" and if I move the screen to the left, I can see the heart rate at certain times of the day.


Same for the Weekly View, for example. It shows the average for the last 6 days and if I tap on one of the points in the graph, it shows the average reseting heart rate for that date.


If I select "Heart Rate" instead, I'm seeing the range of my heart rate during the day, as shown in this photo:

...

...

copied from this article: Monitor your heart rate with Apple Watch - Apple Support


Apple Watch Ultra 2, watchOS 10.6


Nov 23, 2024 8:21 AM in response to gary9000

I'm experiencing the same issue to the point where I don't believe that these monitors are actually reliable and merely a "reference". I have both Ultra 2 and Samsung Watch 6 which I wear at the same time (AW on left Samsung on the right). I track all of my workouts with both watches at the same time and the results are very different.


AW usually reads a much lower heart rate, while Samsung reads up to 20 points higher and several times. My workouts are all out, and I feel that Samsung is where I should be. For example, I jump rope with a heavy rope and go fast. Samsung reads 160 bpm, but AW would read 135. However, I feel more about the 160 than the 135.


Even sleep tracking varies a lot. Both would detect the same amount of sleep, but the breakdown between heart rate, deep, rem, and core sleep would vary. AW would read a lot lower in deep sleep, whereas Samsung would double.


Overall, I am unsure which one to believe and just figured you would need both and find the middle to get an actual result, but who wants to keep having both? I keep reading that AW is more accurate, but after wearing both for a year, I am unsure if that is true. My heart rate for my feelings about Samsung seems more precise, but the feeling is subjective.


Not sure if left and right arm make a difference even though it's calibrate accordingly and conditions are the same for both beside the location being right and left arm

Jul 19, 2023 10:35 AM in response to gary9000

Hello gary9000,


It sounds like your Apple Watch Ultra isn’t measuring your heart rate correctly. We know how important this is for you, and we will help get you to the right place for answers.


The first thing to try is the steps listed in this support article. These steps can often resolve Apple Watch measurement issues:

Get the most accurate measurements using your Apple Watch - Apple Support


If you need continued assistance, please get in touch with the Apple support team via this link: Get Support.


Farewell!


Jun 9, 2024 2:45 AM in response to gary9000

Totally agree. My AWU2 oHR is usually nowhere near my Suunto and connected Polar H10. Oftentimes 20-30 beats below my true HR. As an ultrarunner I know my normal HR pretty well and I've been beyond disappointed with the Ultra. If it wasn't such a good "everyday life" watch I'd get rid of it and not look back.


For everything sports related I'll gladly stick to my Suunto's and Garmin's. I know they're reliable and at least far more accurate.

Heart rate wildly inaccurate on Apple Watch Ultra

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.