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

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

The distance does not change and stays at zero, as do the calories. This issue occurs only during outdoor activities. GPS works fine, the problem is keyed to a software issues.

• 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.

I have already taken the watches (Ultra 2–3) to Apple service, and no issues were found.

• 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.

The malfunction occurs exclusively during outdoor walking or running. The issue begins immediately when I select the workout: the heart rate stays at zero, as do the distance and calories.

Let me summarize what is happening, because from what I read it is not clear and the timeline of the posts is very difficult to follow.

The Ultra 3 (currently in my possession), and previously the Ultra 2, have no hardware issues. This was confirmed by Apple technicians after the watch was sent to the Apple service.

The problem occurs only during outdoor walking or running, and it appears randomly as soon as the workout is started. Along with heart rate, the watch does not record distance and does not calculate calories—all values remain at zero.

The only solution is to power off and restart the smartwatch, without performing any other action. I do not change the position of the watch on my wrist, or reset to factory settings. A simple restart temporarily resolves the problem.

This is the third ULTRA watch I have owned. One of the Ultra 2 units was replaced by Apple due to the same issue, yet the problem reappeared even on the replacement device. I have done everything possible: provided videos, sent photos, and shared all evidence with Apple Support and the service center, but the issue remains unresolved.

I sent my watch to Apple twice. Each time, they kept the smartwatch for only one day; I do not know how extensively it was tested, but this duration is certainly insufficient for the issue to manifest during their diagnostics.

This is not an anatomical issue related to my wrist, because if it were, I would experience problems with other types of workouts as well—which I do not.

Regarding notifications, the issues started with the update to iOS 26; prior to that, everything worked correctly. Even Apple Support does not know what is causing this behavior.

In conclusion, in my humble opinion, this is a software bug that no one is currently addressing or attempting to fix. I use the watch exactly as it was designed to be used: running, walking, swimming, gym workouts, climbing cycling and so far these are the only problems I have encountered.

What is most frustrating is that Apple is doing nothing, despite the fact that I have been using an Ultra product for 15 months and have had issues from the very beginning.

I am now waiting for the next software update, but I am confident that the problem will return.

P.S. Today the issue occurred again after 4 days.

Ciao Steve

My case is different from yours. It also happens to me occasionally that the heart rate turns grey and stays fixed on the last detected value, but all the other metrics like distance and calories keep increasing. After a few seconds or minutes, it goes back to normal.

In my case, the ECG and heart rate during any other indoor or outdoor workout work normally, never a problem. It only happens with OUTDOOR running or walking. I start the workout as soon as I leave the house and begin my run or walk, and the heart rate isn’t read while distance and calories stay at zero. I turn the watch off and on again, and everything goes back to normal.

It’s not a configuration issue because I’ve unpaired and paired it multiple times, and APPLE SERVICE even replaced the device with a new one. Still, the problem keeps bothering me, and Apple can’t find a solution, either at the store or through service. I even wrote to them directly and never got a reply…

Jeff Donald wrote:

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?

I think that if the anatomy of my body were not compatible with the Apple Watch, then this issue should occur with any type of activity, whether indoor or outdoor. Instead, it happens randomly only with one specific workout. I never have any problems on the treadmill, indoor bike, at the gym, or when cycling. It only happens with outdoor walking or running, and always at the moment I start the workout. Therefore, I believe my physical has nothing to do with the problem.

I’ve been to Apple multiple times; at this point I can’t even walk in without them looking at me strangely because of how many times I’ve gone to speak with the manager. Nobody is able to explain what the problem is. If Apple at least tested it for several weeks, they would definitely find the issue, but every time they’ve sent the watch to the service center, they only tested it for a few hours.

steve626 wrote:

Gabriele-Coren wrote:

I think that if the anatomy of my body were not compatible with the Apple Watch, then this issue should occur with any type of activity, whether indoor or outdoor. Instead, it happens randomly only with one specific workout. I never have any problems on the treadmill, indoor bike, at the gym, or when cycling. It only happens with outdoor walking or running, and always at the moment I start the workout. Therefore, I believe my physical has nothing to do with the problem.

It's the unique combination of the Apple Watch hardware, software, sensors, and your specific physiology, how all those things come together and interact. The fact that you have seen this with multiple watch units seems to indicate that it is not specific to one device. But the general Apple "method" (algorithms, sensors, software, hardware) are likely similar for different Apple devices. What you have experienced may be indicating that it is time to explore other brands to find one that works better for you. Some people have experienced something similar to you with other grand devices as well. Frankly, given what has to happen to detect and reliably measure a heart rate from something on one's wrist with movement, jiggling, etc. I'm surprised it doesn't work a lot worse than it does.

I'm not looking for precision in reading the heart rate, also because I wouldn’t even know how to verify it without using two different devices. What matters to me is that the watch works and is reliable over time. What I see is that, despite the many times I’ve sent the watches in for service, and the times I’ve reported the issue online and to Apple Support, nothing has been done yet. And I’m not the only one with this problem.

I’ve spent almost $1,800 on Apple Watches, and I have a tool that on paper is top‑of‑the‑line (and from my point of view it truly is), but if I have to use it only for fitness purposes, then I might as well go back to different brand, where a watch that costs just over $200 is more reliable and the battery lasts much longer.

But since I paid for a premium product, I expect it to work like one.

I’m using the Ocean Band too, and the position of my Ultra 3 is always the same when the issue occurs. I’ve tried moving it further up the arm as Apple support suggested, but it didn’t help. When the heart rate reading drops, the number turns light gray and stays stuck on the last recorded value. All other metrics like distance and calories continue to update. For me, it happens right at the start of the workout, just after the countdown: heart rate isn’t detected, and the rest of the metrics stay at zero—only the time keeps running.

I’m not sure whether the issue originates from the heart rate measurement, but it does seem so to me, since calorie calculation depends on it. As you correctly pointed out, the distance covered is linked to the GPS, which is not working during the workout.

However, the hypothesis that everything starts from the heart rate not being detected was communicated to me by Apple.

I start the workout manually myself, so it is impossible to assume that it was not initiated. Today, the issue occurred once again.

In my case, during an outdoor walk or run, when I start the workout the heart rate is not detected at all. Two dashes appear with an animated red heart, and it stays that way the entire time. Distance and calories show 0.

If, on the other hand, distance and calories are counted and measured but the heart rate is not, after a few seconds the heart rate is detected; in that case, it’s just a delay. However, normally, when the issue does not occur, the heart rate is detected after a few seconds anyway.