How the Apple Watch Tracks Your Sleep (Scientific Review)

[@TheQuantifiedScientist]

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[@kroz7682]

Great video. Would you say the series 4 Apple Watch is still accurate or is it time to get the 9 ?

[@RayanMufti]

What’s Super Sound?

[@danielmoksmann5654]

Waiting anxiously for your review of: - Galaxy Watch 7 - Galaxy Watch Ultra - Galaxy Ring (Maybe in the same video)

[@excog_artem]

The Galaxy ring is the most important one, I think. It is its main selling point.

[@ama-tu-an-ki]

Yes, Watch Ultra has the new upgraded sensors. So far Samsung has performed relatively badly compared to the competition (Apple, Huawei). It'll be interesting to see if they've trained the new sensors on any better data this time around.

[@212roblox212]

Yess Samsung Galaxy Ring

[@tiago4599]

Yeeeeees

[@williams4057]

@@ama-tu-an-ki The regular watch 7 also has the new upgraded sensors too.

[@Etb323]

I’m crying in my Garmin watch. This data does reflect my experience. Sometimes my watch says I had restless sleep but I feel well rested. Gonna stop using the watch for sleeping.

[@donpeleas4780]

in other words, you don't need a watch to tell you whether you slept well or not.

[@TheQuantifiedScientist]

Thanks for sharing!

[@suzzzzzzzzzzzz]

Confirmation bias??

[@ZeDarkLord]

Thank you for making such in-depth videos that are simple to understand. And kudos for putting in all the efforts behind to make it as scientifically accurate as possible.

[@paulstejskal]

Agreed. This is very helpful.

[@thesurfstudmuffin]

This video is an outstanding and detailed review of sleep measurement devices. You can tell he knows what he’s talking about. I’ve done some research in this area and his data analysis is very careful. Thank you.

[@Zomboy4313]

I like how in watchOS 11 it can track sleeping with naps instead of only during sleep focus

[@UnosofManila]

What sleep issues affect the accuracy of sleep trackers? I'd like to know if I am a healthy sleeper

[@danilos7195]

Hello, could you do the test on the new Galaxy Watch 7, with the new sensors? Thanks

[@Ask-Ali]

Would love to see you recover this in the new watchOS update coming this September! The watch can finally track automatically without you having to set up a sleep schedule.

[@Soundwave857]

wait for real? This has been my biggest issue with my apple watch and apple fanboys constantly told me they already do that

[@Ask-Ali]

@@Soundwave857 yup! It’s confirmed. Idk why they’d tell you that lol. That definitely wasn’t the case before

[@andretheseal9837]

Oh thank f**k lol. Im letting my whoop subscription lapse due to too few meaningful updates and the data showing AW being more accurate for some things and on par with others but having to set it to sleep or on a schedule that I might not stick to has been driving me crazy .

[@rutepereira7628]

Same here!

[@Zomboy4313]

@@Ask-AliI think it worked on watchOS 7-8 before they added the more complex sleep tracking

[@MrActiveservo]

So interested to see Galaxy Watch 7 with the upgraded sensors!

[@boyangirginov]

Incredibly in-depth and well presented review; thanks so much!

[@5ervalkat192]

Very interesting stuff. I’ve used an Apple Watch for sleep tracking in the past and found it was terrible. It consistently said I got zero deep sleep, which is incorrect. I switched to a Garmin and though not perfect, the general picture looks a lot more normal. After seeing your video I’m remembering a conversation I had with Garmin about sleep where I mentioned that I move very little during sleep. He said that makes it difficult for trackers to score me and I’m thinking an Apple watch would struggle more due to its reliance on the accelerometer. Just a thought.

[@stevecohen161]

Rob, I appreciate your work and diligence. Thank you ... Steve

Please review Galaxy Ring

[@TheQuantifiedScientist]

Unfortunately Samsung does not send me products, and the ring is not available here, so jumping through hoops to buy one...

[@jamil027]

​@@TheQuantifiedScientistJumping through rings like Sonic

[@markdurand4372]

Great summary. NOW I understand how well these devices perform and compare with one another. Thanks! Now how about a similar explanation for the sleep disturbance and heart rhythm disturbance detection capabilities of the Apple Watch?

[@pubwvj]

I got the Apple Watch Ultra for its scuba dive computer function which is excellent. I have been exploring the sleep monitoring. It shows me as waking up a lot during the night, many short wake-up’s, and sometimes shows me taking much longer to get to sleep than I think is correct. 🤔

[@mixy2647]

It would be great a video reviewing the 3rd party iOS apps that present your Apple Watch sleep data and correlate it against manual entries: alcohol, coffee…

[@ธนกรภูริวรางคกูล]

What kind of sleep disorder are cause effect in this?Could you example plz. thx u

[@JamBox-zy5se]

yeah, I am never still according to every sleep tracker ever, but seem to be pretty healthy.

[@leoceoliveira]

and where can we buy/how much does the dreem eeg device cost?

[@Metalmachine18]

I love the Apple Watch, and love that it’s a great Heart rate and sleep monitor. But it is BAFFLING how bad the Apple Health app is at presenting that data. You’re basically forced to get a third party app if you want to make that data useful.

[@sexypizza7729]

Any suggestions for such an app?

[@deandawiz]

hey, which third party app had worked for you? Im starting to take weight loss seriously and would like a more in-depth view of what my watch is capturing. Thank you in advance.

[@Metalmachine18]

@@deandawiz I’ve played around with lots of them; Gentler streak, athlytic, healthfit, AutoSleep, heartwatch and a few more smaller ones. But the one I settled with is Bevel. Abit more expensive and comprehensive and I like the long term plan for the app

[@lolitsgavin1315]

@@deandawiz Athlytic app is the best in my opinion, it’s almost like whoop in the sense of recovery status and likes all your information into one place. You can pair it with MyFitnessPal to get the amount of calories you’re eating a day into your tracker too

[@Allex46]

@@deandawiz autosleep

[@wowwow2622]

Please review the samsung galaxy ring!!!

[@netmanswe]

The effort you put into analysing all these devices is astounding. Thank you for making it available to everyone.

[@_renze_]

Hi Rob, how good of a job do this smart watch do when sleeping next to a partner in the same bed? Especially the Apple Watch that merely uses movement. Thanks

[@sreejinair]

Hey Rob when are you testing the Galaxy Watch Ultra and the Galaxy Ring.

[@ListonCrest]

The main sleep metric I am intereted in is ”total sleep time”. It would really neat if you could change one of the axis to “total sleep accuracy” to see if any other trackers are better with that perspective.

[@gavriilbs5443]

Very nice testing, but how apple watch se is better than ultra?

[@mariusmander]

Hey I would be very interested in a video that teaches to interpret the health data that the apple watch tracks. Did you make a video or can you recommend a video or literature regarding this topic?

[@DBR6464]

I have the Oura 3 and Apple Watch. They are both great for sleep, but for some reason my Oura ring is usually records 10-30 min less than my Apple watch. I'm not sure which one is more precise. It may be somewhere in between the two. I sleep with both because of the alarm clock on the watch.

[@bliipfert]

Please consider testing the sleep tracking features of the Muse S headband. Thanks!

[@neosam]

Thank you for this video and for putting all the effort in it! Just one question: How do you know that the Apple Watch uses only motion data for sleep tracking?

[@MrAnonimR]

I really hope you will have the time to review the galaxy ring

[@bengodgundam]

Please review the new galaxy ring once its available! felt like Samsung has been doing a terrible job a tracking, would really be informative to know if it is accurate this time

[@DAVIDLEE-ob8ek]

The Galaxy Watch7 was released. It has been announced that the performance has improved a lot. Please compare heart rate..etc with other smart watches

[@TheKix0u]

We'd love to see a comparison between the Oura ring and the Galaxy ring! A video comparing all of the smart rings would be awesome!

[@sharonwood8085]

I have narcolepsy and wondered if you have any idea how sleep trackers would work for someone like me please? Thank you

[@mikayel18ify]

Hi Rob, when do you think you can review the new Samsung Galaxy ring ? Thank you ❤

[@212roblox212]

Can you do a video on the new Samsung Ring?

[@nick024]

excited for the vitals app video!!!

[@johnarildramberg3132]

I’m currently testing watchOS 11, and it’s very very good!

[@lovethytuber4770]

I appreciate your work! Your videos actually answered a lot of questions I had! Too bad some companies have put their respective software behind hefty paywalls.

[@aliticx]

You’re the reason i got an apple watch last month, a used series 9 for $300. I like it.

[@andretheseal9837]

I’m getting 0-30 min of deep sleep with the AW9 after coming from whoop 4.0 which gave me typically around 1.5 hours but as high as 2-2.5. Any ideas? It’s too great of a variance to me to not think something is wrong.

[@shottskies]

Goes to show that these technologies have a long way to go to be reliable

[@shinheejung6258]

I'm looking forward to watch your Galaxy Watch 7 reviews. According to Samsung Electronic, They use new bioactive sensor(They number it as bioactive sensor 3). The difference between bioactive sensor 2 & 3 is a number of LED light (I guess that LED light was increased from 4 to 8). anyway, I can't wait to watch your Galaxy watch 7 reviews and other scientific reviews.

[@smarterphone6863]

Hi can you do a review on oneplus 2r

[@carmig00]

Great idea and nicely crafted review. Just wondering why you picked a rather out dated version of e.g. Garmin Fenix. By now they have version 7, with better sensor technology. You’re comparing it to a fairly new Apple Watch 8. Is this accounted for?

[@Tony_Jesher_07]

Huawei Watch Fit 3 full review, when?

[@OneIdeaTooMany]

This is awesome. I think one addition could be indicating on the graph whether the device requires a subscription in order to track your sleep. I'm on android so apple watches are out of the question but I also don't want to pay a subscription. so that rules out the Oura ring and the H10 I guess..

[@J.Argueta]

Very informative video. I have both the Apple Watch Ultra 2 and the Fitbit Charge 6. I see very, very different data when I sleep and wonder which one of those two is more accurate. The Ultra 2 tends to state I’ve slept longer, and I’m shocked that the Charge 6 says I’ve slept less. Based on how I physically feel (as opposed to emotionally), I tend to think that the Charge 6 is more accurate. Id like to find some confirmation on that

[@bloodrabbid]

And what about people who can't sleep properly anymore? Which way should I at least dig ? Standard recommendations by type - go to bed earlier, do not eat 3 hours before bedtime, etc., no longer work

[@GK-qc5ry]

Fascinating analysis, well done Rob.

[@Mowikan]

I love the apple ultra and I use to own one. But if you are like to swim and do some training the apple watch can’t do something simple as: ever x-lanes(haptic feedback)a warning as long as you swim. Only Garmin can do this. And so i use the fenix7, unfortunately.

[@stephanepecqueux2821]

Waiting anxiously for your review of: - Galaxy Watch 7 - Galaxy Watch Ultra - Galaxy Ring

[@Superfmrs]

Wowww i did not know the skin tempersture vs body temperature differencess! Thankssss

[@ermeriodsassperini]

I'm a little confused by the chart. Is the apple watch better at sleep tracking than the oura ring?

[@BIGaziz7]

do the samsung ring please

[@tamataeo]

Thank you Rob for this amazing video! Just had one question: how can you be sure that Apple Watch doesn’t use heart rate, where did you see that it only uses accelerometers ?

[@MeneerSpaghetti]

I'm still using an Apple Watch Series 6, and I don't find it accurate for tracking my sleep. The Oura Ring 2 also fails to detect when I'm awake during the night. Has the hardware in newer Apple Watches for detecting sleep changed, or is it all similar with just an updated algorithm?

[@Mrgasman1978]

Thanks for sharing all this awesome contents!! So basically, as far as i understood, correct sleep tracking in smartwatches is more related to good softwares and well studied algorithms, than high tech hardware.

[@sendscho2260]

is it just the software of the watchOS that gives the good results? so will apple watch 7,8 and 9 be equally accurate?

[@EgidioLista]

when you're going to review the new samsung galaxy watch 7 on heart activity monitoring and sleep tracking? you're the best, thanks!

[@DrFeelgood1234567]

Thank you. May the algoriddim be with you 🤟🏻

[@joseguzman6988]

Is apple benefiting from location and device activity information as well? They can determine when you are in bed and also since most people check their phone immediately upon wake up they know when you are awake?

[@imbretzy]

Well, you better be good for goodness sake!

[@wschozo]

I noticed Muse S appearing here and there from your videos being used alongside other equipments. How good is Muse S is for sleep tracking by itself? That one seems to be the most available EEG based sleep tracker.

[@정해인-f3n]

I'm really looking forward to the Galaxy Watch7 review you'll

[@giridharjoshi7794]

can you please review Philips smart sleep

[@iliaghp]

Your reviews are amazing! Thank you.

[@smarterphone6863]

Hi please review oneplus watch 2r

[@haziq3636]

Very interesting stuff. Perhaps can you make a video explaining how apple watch and other wearables estimate VO2 Max

[@clarabenedett7275]

Hey hey! I LOVE your reviews! Just got my Apple Watch SE 2nd gen based on your in-depth review. I'm wondering now, is there any App you'd recommend for sleep tracking/analysis with the Apple watch? The Health app is so shallow on the iPhone, I wanted something with more data and recommendations. I'm currently using SleepCycle, Pilow and SleepWatch - all as free versions, to understand which would be best. But I'm wondering if you already have one that you'd recommend? Thank you!!

[@justicerachel]

Do I understand correctly that a key determinant of it working correctly is to provide it with your sleep SCHEDULE. ahead of time? I ask because many people do not have set sleep/wake schedules or have a sleep disorder or other sleep problem. Fitbit is able to properly detect sleep/wake without doing this, even for naps (and catches the sleep stages if you are down for more than 3 hours).

[@stijndevries]

With the next watchOS version it doesn’t need a schedule anymore

[@MonikaSw]

Yeah, tbh my Xiaomi Band 7 could better track the sleep. The AW sleep detection is shit, but the rest is awesome.

[@justicerachel]

@@stijndevries, thank you! I want to make sure I understand. I think you are saying I would need to buy the newest model when it comes out vs. buying one of the existing models that has already performed well in Rob's testing. I am wanting to move out of the Google/Fitbit ecosystem (is the reason I ask), and I don't want to need a subscription.

[@justicerachel]

@@MonikaSw I saw someone saying this same thing on Reddit! Fitbit has mostly done well at detecting my sleep, but sometimes I need to edit the start and end times. Problem is, they got rid of the Windows app, and now they're getting rid of the online dashboard, and I cannot use their mobile app. It's bad.

[@stijndevries]

@@justicerachelno, it’s for all models with the upcoming watchOS 11. It now always runs in the background.

[@taitrieu7879]

Has these watches been tested simultaneously while doing an overnight PSG study? Also, how is it compared when a patient has “normal” sleep vs somebody who might have sleep disorders?

[@captaindcc]

Why would the sleeping disorder affect the results of a sleeping tracker?

[@tmr2757]

The galaxy watch 7 ultra is out , looking forward to your review 👍🏽

[@_busybee23]

Damn, sir. Your in-depth analysis was bang on. Keep up the good work.

[@Kasenkow]

Hi Rob! Why don't you use body composition accuracy as one of the KPIs you compare the devices on? The body fat %, muscle mass, etc.

[@havan17]

Request!!! Can you please also make a comparison for the Samsung Fit 3 vs CMF watch pro 2

[@Kaz-qz2oq]

Would you ever be open to testing the OnePlus Watch 2?

[@shawnspring4824]

I asked too. As an owner of one, I can tell you the sleep tracking is not great, but do find the activity tracking and heart rate tracking to be comparable with my Apple Watch Ultra.

[@ZePedro4259]

Hi Rob! Are you planning on reviewing the Galaxy Watch FE?

[@Me-eb3wv]

Yes

[@JoseTorres-rl3rz]

Apple Watch 10 or Apple Watch Ultra 2 which one is better for sleep tracking?

[@RaniRani-zt2tr]

They are all the same as the series 9 Basically the ultra 2 is a protected series 9 I think it is the same as the series 8 The series 7 does not have a temperature sensor

[@Zufriedenheit]

Thanks for you work. Very Informative! One correction though: In the release notes for WatchOS 9 it says that it uses motion and heart rate to detect sleep stages. So it does not use only motion like suggested in this video.

[@ghostlyskunk4226]

what about the Apple Watch SE first generation?

[@nilsobach2659]

Hey, can you please make a video where you compare the Apple Watch with the Athlytic app against Whoop? :)

[@veganduo27]

does this temperature measurement differ if your living in a country where they use ac in the room

[@DW55n]

I hope you make tease for galaxy watch 6 classic after update oneui 6 . I want see any improvements.

[@bledig]

How does withings nova compare to apple for sleep?

[@MondSemmel]

I really loved the clever intro sequence! And in general, I really loved this video in terms of both content and presentation. This kind of video fits perfectly into your channel, and I'm looking forward to seeing more videos in this style! Finally, to provide some minor constructive criticism, the accompanying music piece at the start of the video sounded extremely generic to me.

[@expierreiment]

I bought the Apple Watch SE 2 based on your findings specifically for sleep tracking. And I have the strong feeling that the algorithm does not work well for my case. I lie away motionless for long periods and it thinks I'm asleep.

[@Edameda_mmori]

Redmi watch 4 review please

[@PeterOleniuk]

Could you review CMF Watch Pro 2 it looks very interesting!!!

[@voodooparadox2513]

Please review the Muse S for sleep. It uses EEG. We want a Dreem headband alternative.

[@MMAneuver]

I second this!!! What's the point in all these trackers that use HRV but don't use ecg and only use optical LOL it's surely a con. Only way to do it must be EEG!

[@brianquigley1940]

I third this. I wear a Muse S headband and its somnographs usually aligned well with the Dreem 2 headband I wore at the same time. (Dreem headbands are no longer consumer products.) I have yet to find a study anywhere that compares the Muse S somnograph with another clinical standard device.

[@MMAneuver]

@brianquigley1940 could you give us an honest review on the muse s? Do you think it's worth it? I'm an athlete and I'd really like to understand and nail my sleep better! (I also have a minor interest in lucid dreaming too)

[@brianquigley1940]

@MMAneuver The somnograph is trustworthy. The device was initially sold as a meditation "helper". I also use it for that purpose. e.g. it shows me whether I nodded off during a session or was in the "zone". The recent update that shows brain wave bands (alpha, delta, gamma, etc.) makes a huge difference. I wore both a Dreem 2 (also used by Rob) and a Muse S for about six months (until the consumer Dreem website was taken down). The somnographs were usually very similar. The main differences were in deep sleep, which were not always perfectly aligned, and the Muse did not record short bathroom breaks on the somnograph. I also wear a Fitbit and Polar watch on my left arm... for the HRV. If I get a decent amount of deep sleep and my HRV correlates well on both watches as high, I know my body is well prepared for a long run. I have two issues with the Muse S headband. The sensory part of the headband wears out quickly. I've gone through FOUR replacements in ONE year, all covered by the warranty. They say they are working on an improved version. The second issue is that the company's primary target audience seems to be... how can I say this politely... the "crystal waving" crowd. e.g. the subscription gives you access to celebrity meditation gurus, etc. Their focus is not on sleep... except for the recent udpate, which gives me hope. You will find a lot of scientific references on their website. They also offer an SDK (software development kit) for people interested in accessing the EEG data, but it's only for iOs. If I could find a commercial EEG product dedicated solely to sleep, I would buy it. I would still use my Muse S for meditation. My guess is that the Dreem 2 and Muse S use very similar hardware. Mind Monitor is an Android app you can download for the Muse. You can monitor your brain waves in real time by bandwidth. I've used it to practice "flattening" my brain waves to train myself to quieten my mind as prep for going to sleep. You can save your data and process it... if you have the necessary coding/analytical skills/knowledge.

[@brianquigley1940]

@MMAneuver I wrote an extensive response and it was deleted! Weird. The somnograph is trustworthy. The headbands wear out quickly within months. The battery only lasts 7.5 hours.

[@wayne1516]

Can you explain why Apple has trouble distinguishing the difference between light sleep / core and DEEP sleep?

[@brianquigley1940]

Only EEG devices can measure deep sleep accurately, which is clearly impossible for watches.

[@SorenaAmini]

Great channel! How accurate are chest straps? Would be interesting to compare it to something that is even more accurate or compare different cheat straps (because if they are accurate they should show similar results

[@5didier5]

Thanks!

[@Buckstein11]

Awesome

[@michael-qp9xd]

Hello - very good info. Nothing shown on Apple Watch below 8. Can comment on motion sensors in apple 6 and lower - ones used from apple 8 and above are much better? Thanks any update here especially on motion sensor in the Apple Watch 6.

[@AdamBloodgood]

Your videos are great! Thank you for sharing and hello from LA.

[@commonmadeholy]

Great video as always thanks! Please could you add to your list to test the Suunto Race S? 😊

[@Shambolic2000]

Great video. Clear and well organised, with useful information and insights. One idea for a future video, maybe you could go through your recommendations for third party apps that do utilise Apple’s dataset well, and compare features/utility?

[@bojtetamas47]

@Rob when galaxy ring ??

[@cr8xtremeCaRnAgE]

I have been using Amazfit Stratos since 2018 and I believe the statistics is accurate enough. I don't need to buy a device that's 4 times expensive and marginally improves details by 10%. It's just sleep, if I am getting enough and captured properly it's all good.

[@Caelo_music]

Really impressed by the Apple watch and I didn't know that they were only using the AC data. Kind of surprised that the others are behind Apple in that regard, since they too should have tons of sleep data to train their models on. Guess Apple engineers are just doing an excellent job.

[@weekendwarrior8179]

I wonder if Samsung will use the accelerometer since the tech is the same?