Issues with incorrect HR readings while running on Apple Watch even with AirPods Pro3

[mahurangi]

transparency and data provenance of incorrect readings during my daily runs

I’m a 73-year-old runner and have run almost every day for years, usually on the same Omaha Beach course.


For the last 6–7 years, across four different Apple Watches, I have regularly observed heart-rate readings that do not match my effort, pace, or how I feel during a run.


Most commonly, the Watch reports implausible heart rates during the first kilometre or so before eventually settling and producing more believable values. Because I run almost every day on a very similar course, I have been able to observe this pattern repeatedly over thousands of runs.


For many years I have also run with a Polar H10 chest strap connected to Strava on my iPhone while simultaneously recording the run on my Apple Watch using the Workout app.


This has given me a long-term comparison between:

• Apple Watch optical heart-rate measurements
• Polar H10 chest-strap measurements

Recently I reviewed one run where the Polar H10 recorded:

• Average HR about 100 bpm
• Maximum HR about 116 bpm

For the same period, Apple Health contains hundreds of Apple Watch readings around:

• 169 bpm
• 170 bpm
• 171 bpm
• 172 bpm

These were not isolated spikes. They were continuous readings stored in Apple Health and attributed to the Watch.


Over the years I have submitted feedback through Apple’s feedback channels and have also emailed Apple executives in an attempt to understand or resolve the issue. Despite this, I have never found a clear explanation of why these discrepancies occur or how users can determine which heart-rate source Apple Health is relying on during a workout.


I have also noticed that some runs show both Apple Watch and Bluetooth heart-rate sources in Apple Health, while other runs show only Apple Watch data. When my AirPods Pro heart-rate sensor appears in the data, the results often look more realistic. At other times it appears absent.

My concern is not that sensors occasionally make mistakes. My concern is transparency and data provenance.

If Apple Health can receive heart-rate data from multiple sources, users should be able to clearly determine:

• Which device generated each reading
• When source switching occurred
• Which source was used for workout metrics and analysis

For anyone using heart-rate data for health, cardiac monitoring, or training decisions, that information matters.


Has anyone else compared Apple Watch workout heart-rate data against a chest-strap reference and found similar discrepancies?

 

[Howard2k]

Yes, lots of people have. The chest strap will almost always be more accurate. Wrist sensors are affected by fit, temperature, skin pigment, tattoos, arm hair, ambient light, and body fat etc.


For the majority, they can work around these issues, but not everybody can.

If it's super important, use the chest strap.

 

[mahurangi]

transparency and data provenance of incorrect readings during my daily runs

I’m a 73-year-old runner and have run almost every day for years, usually on the same Omaha Beach course.


For the last 6–7 years, across four different Apple Watches, I have regularly observed heart-rate readings that do not match my effort, pace, or how I feel during a run.


Most commonly, the Watch reports implausible heart rates during the first kilometre or so before eventually settling and producing more believable values. Because I run almost every day on a very similar course, I have been able to observe this pattern repeatedly over thousands of runs.


For many years I have also run with a Polar H10 chest strap connected to Strava on my iPhone while simultaneously recording the run on my Apple Watch using the Workout app.


This has given me a long-term comparison between:

• Apple Watch optical heart-rate measurements
• Polar H10 chest-strap measurements

Recently I reviewed one run where the Polar H10 recorded:

• Average HR about 100 bpm
• Maximum HR about 116 bpm

For the same period, Apple Health contains hundreds of Apple Watch readings around:

• 169 bpm
• 170 bpm
• 171 bpm
• 172 bpm

These were not isolated spikes. They were continuous readings stored in Apple Health and attributed to the Watch.


Over the years I have submitted feedback through Apple’s feedback channels and have also emailed Apple executives in an attempt to understand or resolve the issue. Despite this, I have never found a clear explanation of why these discrepancies occur or how users can determine which heart-rate source Apple Health is relying on during a workout.


I have also noticed that some runs show both Apple Watch and Bluetooth heart-rate sources in Apple Health, while other runs show only Apple Watch data. When my AirPods Pro heart-rate sensor appears in the data, the results often look more realistic. At other times it appears absent.

My concern is not that sensors occasionally make mistakes. My concern is transparency and data provenance.

If Apple Health can receive heart-rate data from multiple sources, users should be able to clearly determine:

• Which device generated each reading
• When source switching occurred
• Which source was used for workout metrics and analysis

For anyone using heart-rate data for health, cardiac monitoring, or training decisions, that information matters.


Has anyone else compared Apple Watch workout heart-rate data against a chest-strap reference and found similar discrepancies?

A follow-up to my earlier post about Apple Watch heart-rate data.

Today I spent several hours digging into the raw data from the inaugural Warkworth Showgrounds Parkrun, a course that required four hill climbs, including two repeats of the same hills.

The results left me with more questions than answers.
For years I have run with:

• Apple Watch recording the workout
• Polar H10 chest strap connected to Strava on my phone
• More recently, AirPods with heart-rate sensing

The reason I do this is that I have regularly seen implausible heart-rate readings from Apple Watches over the last 6–7 years across four different watches.

Today’s run appeared to show a significant heart-rate dip during the longer third climb of the course.

Initially this looked important because both the Apple-derived graph and the Polar-derived graph appeared to show the dip.

However, when I examined the raw Apple Health data, things became much more complicated.

At the same moment:

• The Apple Watch source was reporting values around 120 bpm.
• Another Apple AirPods poor 3 source was reporting values as low as 55 bpm.
• polar band showing dip but only down around 90

The challenge is that Apple Health stores readings from multiple sources, but makes it surprisingly difficult to determine which source was actually used for workout metrics and analysis.

After several hours of investigation I am left with a simple question:

If two Apple-connected devices are reporting dramatically different heart rates at the same time, how is a user supposed to know which one Apple considers correct?

The more data I examine, the less this appears to be a heart-rate problem and the more it appears to be a data provenance problem.

As someone who has spent a career in IT, I keep coming back to the same principle:

Data without clear provenance is difficult to trust.


I am increasingly convinced that Apple should provide a simple way to show:

• Which device generated each heart-rate reading
• When source switching occurred
• Which source was used for workout calculations
• Why one source was preferred over another

Until then, users are left trying to reverse-engineer the answer from raw data exports.

Has anyone else looked closely at the source-level heart-rate data recorded by Apple Health and found similar inconsistencies?

 

[arc of the universe]

@mahurangi

i totally understand this!
there is no way to know which source is actually being used.

in my case, i have noticed something else, as well.
i occasionally (not regularly, but occasionally) see data in the Health app that are anomalies.
however, in my apps that i use to track my health and fitness (Bevel, Gentler Streak, and Athlytic) data points that are clearly incorrect are never shown and i don't think are being used to calculate their data.
in apple Health, when i check the sources of these incorrect data points that are graphed in the app, i can not locate it.
in other words, it is only the graph in apple Health that is showing an anomaly, but when i look into the raw data in the apple Health app where the sources and values are listed, the data does not show that kind of strangely low/high data being recorded in the range that is listed.
when i delete that data reference in apple Health the graph of course doesn't reflect that anomaly.
so, the written info in the source is correctly ignoring the anomaly by not including it in its written range - only the graph was including that wrong, one-off info.

in my case i pay particular attention to how low my heart rate is recorded during sleep. the lower the better.
in the apple Health app i have seen the graph record a data point of 32bpm which is extremely unlikely.
but nowhere in the source data is that kind of number being reported. only in the graph.
its not within the range that is listed in the Health source data, and, none of my fitness apps seem to record that incorrect data point. its only showing in the Health graph.

finally, for reasons of consistency, wherever it is possible to do so, i choose to allow only one app or device to be able to Write data. in all cases, i choose the Watch as the only source of data. i never allow any of my apps to actually be able to Write basic fitness data such as HR, RHR, HRV, VSO2, RR, VO2max.
for the same reason, i wouldn't choose to allow the new Air Pods to write any of the above data (i don't have Air Pods that are capable of Writing that data, but i wouldnt have them Write it if i did have them). it would be too frustrating for me to deal with that kind of data provenance question.

you mention heat rate beats per minute.
i have found that when i reviewed and compared how apps are setting my Heart Rate Zones, i needed to adjust them slightly to match what i myself was feeling (taking into account all three of these that i feel things: 1 what i am feeling while i am exercising and 2 what i am feeling immediately after exercising, and 3 the way i am feeling for the rest of the day after exercising. i manually set my top range (lowered it) in each fitness app to match my top heart rate that the apple Watch was recording. and had the apps automatically use their own methodology to figure the individual heart rate zones below the top zone. doing this one thing was key to the apps actually giving me data that matched my short term and long term training cardio load scores that actually matched what i myself was feeling. it also made each app's recommendations more attainable and fitting my overall actual condition.

sorry for the lengthy post.
enjoy your running ! 🙂

 

[NoBoMac]

finally, for reasons of consistency, wherever it is possible to do so, i choose to allow only one app or device to be able to Write data. in all cases, i choose the Watch as the only source of data. i never allow any of my apps to actually be able to Write basic fitness data such as HR, RHR, HRV, VSO2, RR, VO2max.
for the same reason, i wouldn't choose to allow the new Air Pods to write any of the above data

This.

Getting device priority order correct is important as gaps in data will be filled in by the other device(s).

And in case of AirPods, even though I don't use them, ditto on would not let them write anything as need to make sure they are fitting correctly. And per link, Watch and pods will try to fill in each other's gaps. In ear buds, for me, just seems like a not great method for tracking: in ear buds get sweaty, wiggle out of position, might not sit right from the get go (current buds I use have been fitting well for years and in the last few weeks, had to change out tips as old tip was not working well in one ear and every tip I've tried since are not sitting well as well).

Forum is full of threads re "weird" Watch readings and generally due to too loose, too tight, sweat causing issues.

Luckily for me, I'm not getting deep into the weeds with tracking so Watch is the only source and as long as things are consistent, I'm ok with what I'm getting/seeing.

 

[AppleForeverandEver]

I love my Apple Watch but have found the HR sensor to be inaccurate at times. I tried chest straps but found the Polar written Sense wrist strap to be easier to put on and take off and has never failed when it came to accuracy. I wear it on my upper arm between my elbow and shoulder. Even works well in below freezing weather.

Polar Verity Sense - Optical Heart Rate Monitor Armband - ANT+, Dual Bluetooth

Polar Verity Sense is a versatile high-quality optical heart rate sensor that measures heart rate from your upper or lower arm or temple. Polar Verity Sense is a great alternative to heart rate chest straps and wrist-based devices. You can use it with the product's armband, or just place it anywh...

www.amazon.com

 

[aleksiz]

A follow-up to my earlier post about Apple Watch heart-rate data.

Today I spent several hours digging into the raw data from the inaugural Warkworth Showgrounds Parkrun, a course that required four hill climbs, including two repeats of the same hills.

The results left me with more questions than answers.
For years I have run with:

• Apple Watch recording the workout
• Polar H10 chest strap connected to Strava on my phone
• More recently, AirPods with heart-rate sensing

The reason I do this is that I have regularly seen implausible heart-rate readings from Apple Watches over the last 6–7 years across four different watches.

Today’s run appeared to show a significant heart-rate dip during the longer third climb of the course.

Initially this looked important because both the Apple-derived graph and the Polar-derived graph appeared to show the dip.

However, when I examined the raw Apple Health data, things became much more complicated.

At the same moment:

• The Apple Watch source was reporting values around 120 bpm.
• Another Apple AirPods poor 3 source was reporting values as low as 55 bpm.
• polar band showing dip but only down around 90

The challenge is that Apple Health stores readings from multiple sources, but makes it surprisingly difficult to determine which source was actually used for workout metrics and analysis.

After several hours of investigation I am left with a simple question:

If two Apple-connected devices are reporting dramatically different heart rates at the same time, how is a user supposed to know which one Apple considers correct?

The more data I examine, the less this appears to be a heart-rate problem and the more it appears to be a data provenance problem.

As someone who has spent a career in IT, I keep coming back to the same principle:

Data without clear provenance is difficult to trust.


I am increasingly convinced that Apple should provide a simple way to show:

• Which device generated each heart-rate reading
• When source switching occurred
• Which source was used for workout calculations
• Why one source was preferred over another

Until then, users are left trying to reverse-engineer the answer from raw data exports.

Has anyone else looked closely at the source-level heart-rate data recorded by Apple Health and found similar inconsistencies?

Just checked my run this morning in the Health app: source for heart rate monitoring switches repeatedly (for longer durations) between my AWU2 and connected airpods pro 3 (bluetooth symbol is used). Values seem to correspond, no anomalies.

I must say that I am impressed by the accuracy of the heart rate monitoring. I often run with a Garmin connected to an HRM strap and average heart rate recorded by my AWU2 is usually exactly the same as the Garmin. I know Garmin switches between optical heart rate and chest strap depending on what it considers most accurate. I would presume AWU does the same?

 

[BigMcGuire]

I've used chest-straps and other monitors before. I've used the Apple Watch since the Apple Watch Series 3. As a very large and hairy man - I have to shave the back of my wrist for the heart rate reader to be consistent - or it just fails to read.

I've had more problems with chest straps than the Apple Watch so I stopped using them years ago. The Ultra watch series has been very accurate for me (I still need to shave the back of my wrist tho). But I have not used a strap with it (only the normal Apple Watch back when I had one.

 

[mahurangi]

Today My Heart Rate Was 193 and 103 at the Same Time

For the past few months I have been on a journey that started with concern about my heart and is increasingly turning into an investigation of technology. Results of my daily runs early April runs caused me to be concerned something unusual was happening physiologically. The evidence has gradually been pointing elsewhere.

This morning's Omaha Beach run provided one of the clearest examples yet.
Since Saturday, I deliberately simplified the setup. No Polar chest strap. No heart-rate recording from Strava. Just my Apple Watch, my AirPods, and music playing from the Watch itself.

After the run I opened the raw Apple Health data and started looking through the recorded heart-rate samples. What I found was remarkable.
Between approximately 6:31 am and 6:42 am, Apple Health was recording two completely different heart rates at the same time. The Bluetooth source (AirPods) was consistently reporting real values around 97–109 bpm, usual for my usual Omaha Beach run.

At the exact same timestamps, the Apple Watch source was reporting values around 180–195 bpm….
Examples included:
- AirPods 97 bpm, Watch 194 bpm
- AirPods 100 bpm, Watch 192 bpm
- AirPods 103 bpm, Watch 193 bpm
- AirPods 105 bpm, Watch 184 bpm
It persisted for over ten minutes.
Then Around 6:42–6:44 am the problem simply vanished. The AirPods continued reporting around 106–109 bpm, and suddenly the Watch was reporting 107–108 bpm as well. From that point onward the two sources were essentially in agreement.

As an IT manager of over 300 Apple devices and BYOD at my school, I find this disquieting.

Apple Health contains two data stream showing that I was around 100 bpm and 190 at the same time. Both values cannot be correct.
A few months ago I was asking, "What is my heart doing?”, Today I am increasingly asking, "What is this technology doing?"
My cardiology reviews, running and exercise tolerance remain stable. My symptoms remain absent.

The one thing that has proved unpredictable is not my heart. It is the technology trying to measure it.

Solution. Apple needs to improve the algorithms to actually discount obviously incorrect readings and go with a more realistic result considering I run every day on the same beach course so I have all things pretty consistent except the inconsistent readings from my watch. It would be great for apps and or users to be able to select Bluetooth AirPods as the default rather than have to depend on getting it from the health app.

 

[BigMcGuire]

I've used a LOT of Apple Watches since 2017 - and I have a lot of friends/family with Apple Watches who don't have problems like this with their Apple Watch. The problem I do have is that if the band isn't tight enough, it won't read heart rate at all (doesn't help I wear it so close to my hand).

Some questions - is the sensor area clean? Relatives I know often never clean that area and it can be pretty gunky.

That's a MASSIVE difference in heart rate readings. I went on a 2 mile run this morning and maxed out at 174 - but for about 20% of the run my band was too loose and it wasn't reading heart rate for that time. 😛 (Not normal for me, but I wore the watch on a looser notch than usual).

Hopefully someone can help. Maybe it is a defective unit on the AW?

 

[Madonepro]

Today’s run appeared to show a significant heart-rate dip during the longer third climb of the course.

Have you compared your heart rate to your running cadence? Sometime Optical HR's get a lock onto your cadence, and report that heart rate.

Can I suggest you visit DC Rainmakers website, and get in touch with him. He'd be able to look at your data, and analyse it for you. His business is reviewing devices, and he loves to dig deep into the nitty gritty of data.