Apple Watch Heart Rate sensor not giving proper readings during intense exercises like P90x3 and Insanity

I have the exact same issue. It's so disappointing. I would love it to just work. I've been back to Apple and they think it might be a hardware problem. I didn't return the watch yet because I hoped that watchOS 2 would fix this issue. It's actually gotten worse. I will return the watch and will demand a replacement as it has never worked from day one (they want to send it in for repair, not going to happen). I truly hope it's just a hardware problem and the replacement will work fine. But I'm afraid that this time Apple truly can't deliver what they promise. And I'm angry about it. Really angry. The sport function is the most important to me and they had slick promotional video's about the sport function. You even see a guy doing a cross fit workout sweating and jumping around. If the replacement doesn't work I'll return the watch completely. I'm not the guy that makes a scene in a store but I feel kind of sorry for the genius that gets my appointment.

UPDATE: After many AppleCare+ conversations, I took my watch into a store. It's now out for "health sensor" repair.

I am beginning to believe the Watch will never be able to get a good reading during certain exercises. Apple mentions boxing specifically, but I can see how P90x would result in similar problems.

As far as lifting weights goes, it seems that the "bent wrist" theory is the most prevalent. Your wrist is bent and therefore bloodflow slows. Related info says that non-rhythmic arm movements may also cause issues.

Ironically, the Fitbit Surge (which offers a weight lifting workout option) has a bit more info on how to get more accurate readings during weight lifting or other non-rhythmic arm motion exercise: 1) wear the device higher up on your arm 2) don't wear it so tight that it might be constricting the blood flow 3) keep your arm still post-exercise rep (not possible during P90x because you never really stop). Then goes on to say that it uses your heart rate trend over the course of the workout. I found that keeping my arm still does sometimes result in the HR jumping up into a realistic zone.

All of this is really a moot point because Apple says that the Other workout just ascribes the caloric burn of a brisk walk. I.e. it's not using heart rate to calculate calorie usage anyway. That said, it would still be nice to know what my average HR is, so I can work to increase it.

Did I just see an Apple Watch ad that touts the heart rate tracking feature that shows a person boxing???? WTH, Apple?!

"Motion is another factor that can affect the heart rate sensor. Rhythmic movements, such as running or cycling, give better results compared to irregular movements, like tennis or boxing."

I too am disappointed in an expensive device I had hoped would rid me of the Polar chest strap. I've been doing T25 workouts for the last couple of months and had some sneaking suspicions that my HR was off on the Apple Watch. Today I wore my Polar chest strap and compared the results to my Apple Watch. In the same 28 minute workout the AW reported Avg BPM of 102 and Total Calories of 250. The Polar chest strap reported Avg BPM 151 and Total Calories 403. That's an almost 50 BPM difference. Wow! I hope Apple can solve this with an update in the near future. I'm glad to see I'm not the only one with this issue.

Last week my Apple Watch was replaced by Apple. Nothing but kudos for the replacement process which was perfect. The Apple genius was kind and understood the problem. Sadly the replacement has exactly the same issues. The only sad conclusion is that the Apple Watch is totally unusable as a serious sport watch for accurate heart rate measurements. Especially with extreme workouts like Insanit, T25 and P90X. It's extremely disappointing and it's the first time I feel an Apple product has completely let me down. Especially if you take the multi million test facility in account and the nice slick promotional videos in which you see a guy work out with ropes and doing fast push-ups. It almost feels like a scam as the sport and fitness function was one of the main reasons I bought the watch. I can't really tell what's the problem. It seems to have a hard time to keep up with intense workouts but I can't figure out why. Sure the watch moves a lity when doing push-ups but the watch is tightly fit around the wrist. Maybe it's sweat between the sensor and the wrist. My biggest fear is that the sensor is just not usable for this kind of exercises and never will be.

It seems as though the issue is that it's only picking up every other heart beat. Sometimes it picks up all beats - other times the number is about half of what it should be. I'll be doing a circuit training routine in the gym and the heart rate will read around 85bpm.... yea no, it should be more like 170bpm. I get the sense that it starts to make assumptions about what constitutes a proper beat, vs. 'noise' or who knows what, and ends up elmininating half the beats. It's pretty useless for heart rate in my opinion, which then questions all of the other metrics such as active calories etc. Very disappointing.

I'm having the same problem with treadmill walking. Much of what has been said applies to me as well. I sweat a lot because I am working hard. While I'm only walking at 4 MPH, the bed is inclined at 7-10% grade. I do this for an hour. By the end my HR is in the 150-155 range. I'm 66 years old so that represents about 90% of my Max Heart Rate Range (resting HR 44, max 164). The craziness usually starts about 30 minutes into my workout when my HR is in the mid 140s. When I look at the HR data afterwards I see where it suddenly went from say 144 to something in the 70s or 80s. It will stay there for anywhere from 1 to 5 minutes and then will just as suddenly jump back to 144. This usually happens at least once in every workout, sometimes 2 or 3 times. I don't believe movement of the watch is the issue. I wear it snug so as not to miss the taps, and my arm movements are relatively slow and rhythmic. Maybe as others have suggested it's the sweat. I don't know.

I Have the same problem with rowing on a Concept2 erg which does have rhythmic motion and for which Apple has a setting in the exercise app, there are times the watch is accurate and times its laughably inaccurate. I had hoped the Watch would replace my polar band. Sadly no way. I'm generally well pleased with Apple products but as someone interested in my fitness and need good data the Apple watch is disappointing and boo on Apple for pretending otherwise.

Very inaccurate for me while cycling. I wear a Wahoo Tickr and that reading is way different (and correct). Apple needs to fix this.

As I came to the sad conclusion that the Apple Watch will never provide any accurate readings anytime soon I bought a Bluetooth Polar chest band. Very unhappy that I need to wear it as I had hoped the watch would free me of those annoying chest bands but very happy with the accurate readings and that the correct readings are finally filling the rings. At least you can use external monitors which is the only silver lining.

Someone mentioned leaving the strap relatively loose and sliding the watch up your arm a bit. I tried this, I moved the watch 1-2 cm towards my elbow from where I usually wear it and this seems, after some but not extensive trials to have improved the hr accuracy a great deal. Perhaps its an issue of the watch finding a part of your arm where it gets a good read. If you're frustrated with the AW HR accuracy try it to see if it helps.

I purchased an Apple Watch almost a week ago and I've quickly come to learn the apple Watch isn't ready to function as my primary device for measuring my heart rate during training sessions. Wildly inaccurate and sometimes the workout app just freezes and doesn't provide a measurement at all. When standing still the measurements from the Apple Watch match up perfectly with those fromy my Polar sensor. For whatever reason irregular movement throws off the Apple Watch's ability to provide an accurate reading. From the quick research I've done this seems to be an issue with all watch based heart rate monitors. For now I've paired up a Polar H7 sensor with my Apple Watch and it works perfect. Accurate readings and the Watch uses a lot less battery (for a 1 hour training session using the H7 sensor the Apple Watch used about 5% battery life vs 15%-20% using the Watch's built in sensors). I could do without having to wear a chest strap sensor but until technology becomes such that watch based heart rate monitors are more accurate than strap based sensors I'm ok pairing up my Apple Watch with a strap sensor.

Otherwise I've been pleasantly surprised with how much I enjoy the Apple Watch!!!!

I was surprised today when my iPhone rang with a call from Austin Texas (I live in London UK). I don't know anyone in Austin. Turned out it was someone from the iOS Apple Watch team calling about my problems with the HR reading silliness on the watch. The person I spoke to had been given a list of questions from AW engineers which we spent about 15 minutes discussing (how tight the watch was, which arm, how often I had problems, what kinds of workouts, etc etc). Then they emailed me some software to install on my watch to log what was going on with the watch and talked me through installing it.. Then they had me work out while running the workout app with this logging software. For a person my age (68) using standard formula my MHR is around 155ish. I started my workout pretty intensively and soon my heart was pounding and I knew I was working out in the 85%+ range of my MHR. The watch initially read 128bpm then sank to 65bpm in less than a minute and stayed there and wouldn't budge until about the 7 min mark when the HR rate reading went grey and then shot up to 147. After that it stayed accurate or at least what experientially felt like accurate.

Afterwards they called me back and talked me through uploading the diagnostic file to them and erasing the software from my watch. They really spent a lot of time with me, especially considering the international call (ok, $202B in cash but still...). The chap I spoke to was genuinely concerned to get as much info as possible and kept saying they wanted to get to the bottom of the problems. Depending on what they find they'll either contact me (I guess if its an individual problem) or try to fix the problem in a software update.

So there is hope that Apple is working to sort these issues out. I was impressed. Thanks to the watch team if they read this!

Eric

Same happened to me this night and I was amazed to see a call coming in from USA, Texas. I don't know anyone there too so I was pretty amazed too. Unfortunately I was 1 second too late to pick up the phone (was bathing my kids). I kept wondering who called from Texas but now I know! Very interesting to read. Should someone from Apple read this: give me another call, happy to help too 😉

On a more serious note: I now work out in two ways: running with just the watch and an iPhone and T25 with chest band (Polar H7) and Apple Watch. Both give good readings now. I gave up on just exercising with Apple Watch as I experienced the same odd drops in heart rate readings all too often. Discussed the issue with AppleCare two times now (once in store and once in a chat). They alrelady replaced the watch (express replacemen, great service!) but unfortunately it didn't solve the issue. I hope they can fix this by a software update but that would be a miracle in my opinion. Maybe better sensors can fix this in a new model but I'm doubtful the current gen will be able to provide good readings in really extreme exercises (and in all honesty, T25 gamma (which I do now) and insanity and P90X are pretty extreme). Happy to see Apple is at least investigating the issue. If a tech guy reads this and needs some data I'm happy to provide it. Saved loads of it already for the AppleCare guys.