Persistent Heart Rate Monitoring Issue on Apple Watch Ultra 2 & 3

The only time my Ultra 2 loses the heart rate during workouts like Outdoor Walk and Outdoor Cycle, is because the weight of the watch pushes is further towards the wrist due to the movement of the arm.

When I wear it 1-2cm further away from the wrist than normal, there are no issues. Plus, wearing the Ocean Band instead of the Alpine Loop helps to keep it in place.

This also happened in watchOS versions prior to watchOS 26.

Gabriele-Coren wrote:

Heart Rate: The heart rate for outdoor runs or walks remains at zero and does not display as greyed out, as well as calories and distance.

Distance does not change as you run or walk? That sounds like something beyond just heart rate. Distance should be keyed to GPS.

Notifications: This is not a configuration issue; the functionality was working prior to iOS 26. An Apple representative has verified the setup, and everything is correctly configured.

Did the Apple representative then suggest the watch be looked at for service? As the heart rate is not working but the device is properly configured. Did they suggest anything regarding the fact that distance for you was not updating?

When I encountered this, the only measurement that was "interrupted" was heart rate. Which led me to believe that the sensor under the watch against my wrist was not able to detect a heart beat consistently. So to address that I simply adjusted the position of the band and tightened it.

Having read through posts like these, I am concluding that:

• There is individual variation at play here. For some people there is no issue, for others, anatomy or the matching of the watch design to the anatomy is not working as well. For some, adjustments fix the issue, for you this did not work.
• Other brands of watch might work better, although there are reports that this heart beat detection can be an issue for other brands as well. So maybe trying out a watch before buying it is important.
• There may be more than one thing happening here. If heart rate AND distance are not updating, that could be a different issue than heart rate alone. The distance covered utilizes separate sensors and should not be related to heart rate. I could triple my heart rate but if I am moving at the same speed, rate of distance covered should not change.
• It might be helpful for you to bring the watch in for service and hopefully be able to demonstrate the anomaly to Apple in person.
• My Apple Watch (Series 11) is relatively new and has always been on the latest OS so I don't have a comparison with earlier OS versions that I can make.
• You did indicate that your problem only occurs during OUTDOORS workouts. So I am trying to think of what is different for OUTDOORS workouts. All I can come up with is temperature, clothing. The watch really has no way to tell if one is indoors or outdoors, physically. What happens if you tell the watch this is an indoor workout even if it is outdoors? Is the problem the same? If it is, that would point to either temperature or clothing, I think. What else could there be? In some cases, an indoor workout does not use GPS to measure distance, it instead uses arm movement (if GPS cannot be sensed indoors, although often GPS can be sensed indoors). So that might be a clue about the distance not updating, but I think that is separate from heart rate, still.

Seconding Jeff's latest post ... keep in mind that Apple Discussions have only other users are participants. I very much doubt that there is anything left for users (who are only reading about this online, not observing directly) to suggest to resolve the issues with your watches. I think your only recourse is to take the watches to a place that provides authorized Apple service for watches (and Jeff may be right, it maybe needs to be an Apple Store versus a third party authorized provider) and demonstrate the malfunction(s) and request service to repair them. (I hope they are under warranty or AppleCare ...)

I think there isn't much a user can do to "tweak" things other than change the watch bands or their tightness to improve responsiveness of heart rate measurements. The Watch software and OS are basically frozen and not user adjustable, other than through Settings. Barring something like a cosmic ray, the OS and software are identical on all the watches. So something intrinsic would normally cause widespread failures in the very large user community. This is why, based on what you have described in quite good detail, I think you need to get Apple service for your devices after demonstrating the malfunctions in person to the authorized staff.

Hello Gabriele-Coren, I had not seen an update to your watch situation in several days and wanted to share with you some things I have recently learned as I continue to get familiar with how these Apple Watches work. I have had mine for about a month and a half only, so I am new at this. Mine is a Series 11.

I had noticed sometimes, usually at the beginning of an outdoors bicycling workout or outdoors walking workout, that my heart rate was not registering. The rate was greyed out and the little red heart image was circling, as if it were looking for a signal I am guessing. I realize this is not the exact same symptom you had noticed; also you have a lot more history with this than me. Because for me, when the heart rate wasn't registering, the distance covered and timer and other metrics WERE being recorded and updating.

Here is what I did and mine is working reliably now:

• When I wear the watch around the home or out and about or asleep but NOT exercising or doing a "workout," I usually have the watch on the third hole (simple rubber sports band). This is moderately loose, but it always registers heart rate, including during sleep. But for "workouts," which even for walking involve some jostling about (and for bicycling some bumpiness), I have started to tighten the band by one hole (second hole). This holds it noticeably tighter and does not allow much movement on the arm at all. I believe this has eliminated any periods when the heart rate doesn't show. But the looser (third) hole on the band for me still works fine for sleep, and non-workout activity.
• I have started outdoor (the only kind I have been doing) workouts now before I start moving. The Watch immediately notices I am not moving and pauses the workout ("workout paused"). But the heart rate seems to register almost right away. My "theory" here is that it takes some searching for the sensor to "find" and "lock" onto the heart beat through the skin and when I am not moving at all, it locks onto it much faster, versus searching for some ~ seconds to ~ minutes while in active motion right away. My theory may or may not be correct.
• Once in a while, rarely, I have still seen the heart rate go away in the middle of a ride. Most rides, which last 2 hours or so, it stays locked up for the entire time. But once or twice it "lost" the heart rate but when I stopped at a traffic light, and the workout "paused" automatically, the heart rate came right back very quickly. I am again guessing that being stationary helps it to "find" the heart rate. So inadvertently "pausing the workout" quickly recovered the heart rate. This isn't something I would want to do very much, but it has only happened a couple times over the past two weeks or so.

So what I do now is: tighten the band during workouts one notch higher than normal; and start the workout when stationary. And in the rare event that the heart rate gets "lost," if I "pause" the workout for just a couple of seconds, it gets found again. When I tighten the band for a workout, it is tight enough that I don't want to keep it that way at other times, it is slightly uncomfortable even. But it works well for workouts of limited duration.

[I also have been positioning the band a bit further way from my hand on the arm/wrist. But I don't know if that really matters.]

With the above changes, I never seem to lose the heart rate measurement anymore.

If it’s not hardware, you believe it to be software or what? Software errors when so isolated (very few reported cases here, Reddit, Facebook groups etc.) are generally only on a few users watches. The solution is to unpair the device, setup as new, do not add any additional apps etc and pair the device to your iPhone and test the device for several weeks to confirm operation.

Gabriele-Coren wrote:

The malfunction occurs exclusively during outdoor workouts (typically walking or running). With both devices, the issue generally begins approximately three weeks after the watches were purchased, then escalates to weekly occurrences, and then becomes almost every two days.

The heart rate stopping to update and showing "gray" is something that others have reported. There are even YouTube videos on the web on how to "fix" this. However I think the cause may be different for different people.

My Apple Watch Series 11 has never stopped updating heart rate during outdoors walking workouts. However I do longer bicycle rides (2-3 hours) and I did notice that sometimes (not often) the heart rate stopped updating during bike rides. The temperature was cool (below 60 deg F for bike rides; below 32 deg F for some of the walks). What worked for me was to (a) tighten the band by one hole; and (b) shift the watch/band down the arm further away from the hand/wrist by 0.5-1 inch. After that it worked properly, except for one time, and for that one time I shifted the watch/band up the arm (away from the hand) during the ride and the heart rate monitor returned to normal function. That makes me believe that at least for me, the tightness of the band and its position needed to be tweaked. In addition, before I made those adjustments to fix the issue, I found that if the heart rate went gray and stopped updating, when I stopped my bike at a red light, the workout automatically "paused" and then when the light went green and I started riding again, when the workout automatically resumed, the heart rate returned. So pausing the workout and resuming it seemed to instigate a recapture of the heart rate data. I later saw a YouTube video about this issue and the person making the video recommended doing what I had already found out, namely pause then resume the workout. I don't consider pausing the workout a long term acceptable solution, it interrupts things and impacts what is being measured.

Additionally, since the latest iOS 26 update, notifications during workouts are no longer functioning, despite being enabled.

That sounds like a different problem, possibly in the setup/configuration. Or, if these are notifications like ones from messaging, maybe the cellular signal is weak or the connection to the iPhone (if the iPhone is being carried) is somehow impaired. I have strong cellular signals where I go and I get too many notifications, frankly, I may have to figure out how to cut back on them. When you say notifications are no longer functioning, are you referring to notifications that are over the air, or notifications from the watch about the workout. Mine is always announcing when I have walked 1 mile, or every 5 miles for bicycling, with average speed and so forth being broadcasted. I also see sports scores and headlines on my Apple Watch along with emails and texts, during workouts, so I know those are coming in over the air as well.

It sounds like, from a more careful reading of your posts, that this workout recording issue (it seems that it is the workout not just heart rate monitor because you said GPS does not register distance nor do calories get counted either) is intermittent, e.g. most of the time it does not occur, but then days later it does.

You posed it originally as a heart rate monitor issue but it seems like the entire workout is not being recorded or updated, not just the heart rate, but all of the workout metrics aren't proceeding. So it seems more systemic. Is anything being updated at all in those workouts when the glitch occurs? Does the watch act like it knows a workout has started? Do you get confirmation that a workout has started (mine counts down and makes little noises to confirm)?

Keep in mind that if GPS is not working when this happens, it will show zero velocity and hence zero calories (only active/workout calories are show, the basal metabolism calories are not included to my knowledge). But ... in my workouts, even if I stop moving or tell the watch to pause the workout, my heart rate updates continuously (I can see it drop from a higher level to a lower level when I stop moving).

So it seems that both GPS and heart rate are not working for you, when this happens. I am wondering if the workout has even been started in those instances.

Because the issue seems to be intermittent, Apple technicians might not be able to reproduce it. In that case, it could be an intermittent hardware OR software problem. Any device's hardware can have an intermittent issue (weak solder joint, faulty integrated circuit, etc.), but since the software is reproduced in billions of devices, a software issue seems less likely. From what I have seen online (there are scores of YouTube videos explaining how to "fix" a heart rate failure to update or record, but none seem to have found a version of this that matches all your symptoms), most of the "solutions" seem to be to pause and restart the workout, or to adjust the watch position. For me, a case of just one, I see the heart rate stop updating only once in a while and I have always been able to bring it back by skooching the watch band up a few mm higher on the arm (away from the wrist). But everyone is different.

Since you are getting no resolution, you should submit a big report: Feedback - Apple Watch - Apple

Along the lines of what Jeff Donald suggested, if you can go to an Apple Store you can try one of their watches on display to see if that watch shows your heart beat when your own watch does not. Or some other store selling Apple Watches, such as Best Buy or other Apple authorized sellers.

If the watches in the store sense your heart rate that seems to point the finger to your own device. I would bring it in for service/check anyway.

Apple does say this about its sensors for blood measurements on the wrist/arm:

• Skin perfusion (or how much blood flows through your skin) can impact measurements. Skin perfusion varies significantly from person to person and can also be impacted by the environment. If you are out in the cold, for example, the skin perfusion in your wrist might be too low for the sensor to work ...
• Permanent or temporary changes to your skin, such as some tattoos, can also impact performance. The ink, pattern, and saturation of some tattoos can block light from the sensor ...

Medical people who draw blood samples also know that temperature changes (lower temperatures) can make blood vessels smaller on some people, not so much on others ...

I have long had this issue with previous apple watches. I really thought that the Ultra would simply resolve such an issue, but no. Sadly not.

I will try and help with this by experimenting and reporting back as I work through this. It’s either that or I move away from the Ultra, which would mean really moving away from the Apple ecosystem as far as I am concerned.

My learnings from this thread and many other places I have found discussing the same issue:

• This is not simply an Apple issue. It is pretty much true of most brands and this type of technology. There are options for wearables that can do better, but that for me would be (as I mentioned above) leaving Apple entirely.
• The location to get best results on the wrist is to have the device sitting with the edge of the device against the “pisiform bone” i.e. not allowing any of the device to go any closer to the wrist that that.
• Wear a strap that will hold the watch in the best position (I have always worn sports bands but the plastic style material definitely does not hold the watch in place). I will try the really boring Apple Trail Loop next to see if things improve.
• Make sure the device can have really good constant contact with your skin. I have pretty hairy (and fine dense hair) in this area so will gladly be the test dummy to see if shaving the area helps (that is if the new band and positioning does not work!).

Let’s see how this goes and I will report back with findings in the hope they help others with this same and frustrating issue.

Do you know anyone else with one of the Apple Ultra models and would they allow you to wear their watch for a short while to see if you can duplicate the issue on their Watch? If not, how close are you to an Apple Retail Store? My thinking is to determine if the issue is the Watch or a physiological (incompatibility) with you.

An Apple Authorized Service Provider is not the same as an Apple Retail Store. Do you have a nearby Apple Store that you can visit and compare watches? You’ll need to partner with a member of the store management team. But you would be able to walk outside and demonstrate the issue to one of the Genius’ and/or a manager so the issue can be observed and then addressed.

Hi, as I suggested before, partner with an Apple Store Manager about your issue and the frustration you’re having. Listen to what the manger suggests and determine if any are viable solutions for testing compatibility of Apple Watch with your particular needs and body type.

Your issue is so specific and intermittent in nature that routine diagnostics will probably not identify the true issue for weeks or perhaps months. The answer may be that Apple Watch and its finely tuned sensors are not fully compatible with your body’s exact physiological characteristics.

The ultimate answer might be, current Apple models will occasionally fail to detect your body’s heart rate. Apple (or any manufacturer) can’t make a wearable device that works perfectly for all 7.5 billion people all the time and be accurate 100% of the time.

Your thoughts?

Well for anyone interested, I really thought I had the nut cracked but no. The issue I am trying to resolve is the inability of the watch to maintain reporting on my heart rate. Through this testing, I have found another foible of the watch. Read on.

• Swapped to the trail loop band which DID at least keep the watch in place. Win.
• Keeping the watch in what was certainly a more reliable position (sitting with the edge of the device against the “pisiform bone”) but did not really provide a constant heart rate reporting, with the watch constantly greying out the heart rate and occasionally jumping back in with what was not always a correct reading (verified against an alternate heart rate monitor running in parallel)
• Shaving the skin to provide a cleanest possible surface for contact - really though this would have fixed it. Nope. NO DIFFERENCE whatsoever.

I always clean the watch thoroughly before an exercise routine as I have certainly found that this does make a difference to reliability.

My findings leave me thoroughly disappointed in the watch. I will be relying on a paired heart rate monitor as this device does not do the job even remotely close to good enough.

What else did I find that was odd?

I found that on a treadmill, running at precisely the same speed, that the position I held my arm/hand greatly impacted the pace reported by the watch. Worse, even when maintaining the same form and position, the pace jumped between (for example) 9.2 and 10.2 and stayed at one for a period and switched back without me having changed anything. The difference between holding the arms down at sides and holding them up was huge. Very unreliable reporting - period.

Hope this all helps someone. It certainly has helped me. When the watch's life comes to its inevitable end, so will my devotion to the Apple ecosystem and I will sadly be more open to all the alternate techs out there that do a better job.

Apple does not offer support via email or postal service. If you’re in the US, please call  1-800-MY-APPLE, or outside the US, consult the support articles below. In Canada, call 1-800-263-3394.

Contact Apple for support and service - Apple Support

Genius Bar Reservation and Apple Support Options - Apple

Explore Service Locations

Official Apple Support

Did you try to put your watch on your other wrist?