I see this exact behavior. Normal readings appear fine but during workouts my HR shows much higher than it actually is.
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?:How accurate is Apple Watch heart rate reading?
- Thread starter greyhoundrick
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Buy an S4 or S5 from somewhere that allows returns.
My S4 has been fine, and I've also done a number of runs with a Garmin running watch w/ chest strap. HR figures were always about the same, +/- 1BPM.
Ok. So that’s interesting- and I was really hoping to get a reply like that. You’ve given me the fuel I needed to upgrade (or justify the purchase to my wife). Will wait until I see AW5 in store and then do a side by side comparison with my Tickr and report back. Fingers crossed
Seems pretty accurate to me, Purple is Apple Watch, greeny/blue is Tickr recorded onto an 830 Edge.
link to analyze.dcrainmaker.com
link to analyze.dcrainmaker.com
a second indoor cycle test and I'm happy with the HR readings. This time dcrainmaker told me how to align these better using a 2nd reference point (ie power) and a 3rd FIT file which I didn't do in the post above.
pink is the AW trace, the other is Wahoo Tickr paired to Edge 830.
analyze.dcrainmaker.com
pink is the AW trace, the other is Wahoo Tickr paired to Edge 830.
DC Rainmaker Analyzer
Thanks for posting those, they look pretty solid.a second indoor cycle test and I'm happy with the HR readings. This time dcrainmaker told me how to align these better using a 2nd reference point (ie power) and a 3rd FIT file which I didn't do in the post above.
pink is the AW trace, the other is Wahoo Tickr paired to Edge 830.
View attachment 863473
DC Rainmaker Analyzer
(as an aside, folks are advised to remember Segal's law ...
)
The ECG part should be quite accurate.
The pulse portion will vary and has trouble with continuous HRV required for certain analyses.
The wrist is a very difficult place to get pulse. There is a lot of noise with low signal levels. There will be a great degree of variation based on the tightness of the watch band, the color and hairiness of the skin, and the level of perfusion.
The watch overall does an admirable job getting decent data for most circumstances. But motion and perspiration will interfere at times.
The pulse portion will vary and has trouble with continuous HRV required for certain analyses.
The wrist is a very difficult place to get pulse. There is a lot of noise with low signal levels. There will be a great degree of variation based on the tightness of the watch band, the color and hairiness of the skin, and the level of perfusion.
The watch overall does an admirable job getting decent data for most circumstances. But motion and perspiration will interfere at times.
I find mine very accurate (Series 4).
I‘ve compared to a few different ellipticals and bikes in the gym, and they always match up. I use a Scosche Rhythm+ monitor when I ride my Peloton and it matches up almost exactly with my watch reading too.
Been very pleased. As others noted - need to have a good tight band and the right placement on your wrist.
I‘ve compared to a few different ellipticals and bikes in the gym, and they always match up. I use a Scosche Rhythm+ monitor when I ride my Peloton and it matches up almost exactly with my watch reading too.
Been very pleased. As others noted - need to have a good tight band and the right placement on your wrist.
I'd imagine they are accurate, especially the ECG.
It's a daily thing for me to get between 2-6 low heart rate warnings with a resting heart rate of 36-41 depending what I've been doing. The Dr's not too concerned as I do quite a bit of running, mountaineering etc... they'd be more concerned with that low a resting heart rate and no exercise.
I do recall having a conversation with the anaesthetist after a knee op I had and he said it freaked them out a little as I was low to mid 30's
Has your cardiologist explained why there would be a difference? What HR do you get using the ECG or when you measure your HR with your finger on the crown?!?
I must be a one-off due to my skin type or color or body composition or some other factor (btw - caucasian male in mid-50's). My AWS4 and now 5 both showed pretty stark differences between heart rates when running. I have a Fenix 3 with a Garmin HR Strap that I wear (have for years) and a pretty standard 4 mile run I do that is pretty hilly. I noticed on the Apple Watches that my HR would never really modulate as much as I was used to (per looking at the watch while running). It would stay in the mid- to high150's for most of my run, where I was used to it coming down on the down-hill portions. Being that I use my HR as an indicator of my current output and modify my pace and effort based on that, I don't like a non-accurate rate.
So I have been wearing both for a few runs and I've attached a basic comparison (I don't have an acct at dcrainmaker to use his tool) of the same run taken a couple days ago on the AW Series 5. This type of discrepancy is common. It wasn't a one-off.
For me - I will be using my Wahoo Tickr now whenever I run or bike. I can'r rely on the watche's HR function for serious training/fitness activities.
(Fenix 3/Garmin HR Strap on the left, Apple Watch Series 5 on the right)
So I have been wearing both for a few runs and I've attached a basic comparison (I don't have an acct at dcrainmaker to use his tool) of the same run taken a couple days ago on the AW Series 5. This type of discrepancy is common. It wasn't a one-off.
For me - I will be using my Wahoo Tickr now whenever I run or bike. I can'r rely on the watche's HR function for serious training/fitness activities.
(Fenix 3/Garmin HR Strap on the left, Apple Watch Series 5 on the right)
Speaking from years of HRM chest strap experience (Polar then various Garmin straps), those have their own set of potential issues as well. Static from certain shirts in dry air, poor contact unless using electrode gel (brrr!!), and ever interference from electrical transmission lines...
Having using Garmin optical HRMs as well as a progression of Apple Watches, I've been very pleased with the S4 and now my S5. I use a sport loop and don't have to do anything special in terms of tightness. Snug enough to not flop around during my runs works fine for me.
Just got my AW5 to do test as described above. First major finding. It will not do ECG for a HR less than 50!!!!
So disappointed. That was the first improvement I was hoping for.
Next - I’ll see how accurate for actual performance work - but already feeling this is not a tool for people with low HRs
So disappointed. That was the first improvement I was hoping for.
Next - I’ll see how accurate for actual performance work - but already feeling this is not a tool for people with low HRs
The heart rate measured by the watch seems to be accurate for me. I have manually counted the pulse at the wrist and compared it to readings from the Apple Watch. They usually differ within 1-2 beats per minutes. My resting heart rate is around 55 bpm. At least it seems to be accurate around that range. But I don't know enough about how optical heart rate sensors are calibrated so whether the accuracy can apply to other ranges of heart rate is unclear to me.
Just chiming in as another cyclist.
I've had the same curiosity of how well can a wrist HR monitor be compared to a chest strap HR monitor. So, I started getting more serious with my cycling lately and bought spin bike this Winter along with a Wahoo chest strap, cadance and speed meters for my pedal crank and wheel hub. In 2 instances thus far, 10 minute ride and a 20 minute ride I've done, the Apple watch average was the same on the 10 minute ride and only 1 beat per second off on the 20 minute ride. So I would say, the the Apple Watch gets it right in regards to HR.
Here are logs, the Left with the green cycle icon is the Apple Watch 4. The orange icon is Strava using a trifecta of sensors including the Wahoo chest strap, speed, and cadance meters.
I've had the same curiosity of how well can a wrist HR monitor be compared to a chest strap HR monitor. So, I started getting more serious with my cycling lately and bought spin bike this Winter along with a Wahoo chest strap, cadance and speed meters for my pedal crank and wheel hub. In 2 instances thus far, 10 minute ride and a 20 minute ride I've done, the Apple watch average was the same on the 10 minute ride and only 1 beat per second off on the 20 minute ride. So I would say, the the Apple Watch gets it right in regards to HR.
Here are logs, the Left with the green cycle icon is the Apple Watch 4. The orange icon is Strava using a trifecta of sensors including the Wahoo chest strap, speed, and cadance meters.
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So I previously reported that I was seeing the odd drop in the low 40’s. I have since tightened the band, and I no longer see these drops.
The drops where single instances and never triggered the low heart rate warning.
Confident having been wearing the band tighter for near on two weeks without a low reading that the drops where due to the band not being tight enough rather than actually have low heart rate Drops.
The drops where single instances and never triggered the low heart rate warning.
Confident having been wearing the band tighter for near on two weeks without a low reading that the drops where due to the band not being tight enough rather than actually have low heart rate Drops.
Probably difference the way Apple and Strava calculate calories burned.
Apple tends to be more conservative in most cases I’ve seen.
how did you find out about this?
i cannot find any info on the Apple help pages.
thanks
Strava had more sensors feeding into it since I have a (1) Wahoo HR monitor (2) a speed sensor attached to the wheel and (3) cadance sensor on my shoe to show how many revolutions I make with the pedals.
Apple Watch only has the HR sensor.
https://support.apple.com/en-us/HT204666
To use the electrical heart sensor to measure your heart rate, open the Heart Rate app and place your finger on the Digital Crown. You will get a faster reading with higher fidelity — getting a measurement every second instead of every 5 seconds. You’ll see "ECG" in Heart Rate Context when looking at recorded data for Heart Rate in the Health app. You can also use the electrical heart sensor to take an ECG with the ECG app.
Thank you. I thought I looked at that page. Obviously I need to pay better attention.
It makes me wonder what else I am missing about this watch.
i’m very different from you guys, i’m a nearly 68 year old woman with no health problems but totally not in shape and i just got a new series 3. i noticed that my heart rate app is acting very weird today. when i first look at it it measures me in the ballpark, around 70, but then almost immediately drops some 20 points between one beat and the next! it was hovering in the forties, so i had it measure again and it was in the 70s, but the next beat 44! is it broken? i don’t feel any differently. i did have a flu shot today, but no reactions to those ever.
To test whether it’s accurate, manually check your pulse at the same time by placing a finger in the corner of your neck or bottom of your wrist. You will feel the jumps. If you do then the watch is accurate and you should go to the ER. If your pulse feels normal then the watch is not reporting your HR correctly.
I just use a chest strap - that way you know it’s basically as accurate as you can get it.