Oura ring vs. Emfit QS (My detailed comparison)

Tags: #<Tag:0x00007fa5edfc9c30> #<Tag:0x00007fa5edfc9ac8>

I just wrote a detailed comparison about the Oura & Emfit QS on my blog!

I copy-pasted everything here, so I can get your feedback on it!

Here is the blog post:

I couldn't decide whether to buy Oura or Emfit QS, so I bought them both for testing!

Convenience

Oura:

The Oura ring is comfortable, but I have to:

  • Put it on and off every night
  • Charge it once every 3-5. days.

Emfit QS:

Once it's installed, I don't have to do anything! Passive tracking FTW!

Winner: Emfit QS

Traveling

Oura:

Size of the box: 8x8x8 cm.
If it's only for a weekend trip, then the battery might be able to last, and you can just bring the ring with you!

Emfit QS:

Size of the box: 18x17x8.5
With the Emfit QS, you always have to set it up by:

  • Placing the sensor under your mattress & plugging it in the outlet (2-5 minutes)
  • Setting up the new Wifi connection (2-5 minutes)

Winner: Oura

It's definitely easier to just bring a ring (and maybe a charger) with you... (you have to use 4-10 minutes setting up the Emfit QS if you want to use it when traveling)

The Oura box takes up 5,08 times less space than the Emfit QS box!

Available metrics

Both have these metrics:

  • Heart rate
  • Heart rate variability (RMSSD)
  • Sleep: Going to bed, waking up, sleep latency, total time in bed & total time asleep, Sleep stage (Deep, light, REM & awake)
  • Respiratory rate
  • Continuous activity score (only in the night for the Emfit)

Oura also have these:

  • Body temperature
  • Steps

Emfit also have these:

  • Toss & turn and bed exits
  • Autonomic nervous system balance (LF/HF ratio)

Winner: It depends...

Oura wins if: body temperature, daytime activity scores, and steps are the most important metrics to you.

Emfit QS wins if : toss and turns, bed exits, and autonomic nervous system balance (LF/HF ratio) are the most important metrics to you, then Emfit QS wins.

Autonomic nervous system balance is inferred through the LF/HF ratio, which is another HRV metric than RMSSD, which is the one that is both used by Emfit QS & the Oura ring.
The LF/HF ratio is assumed to show the balance between sympathetic nervous system activity (SNS) & parasympathetic nervous system activity (PNS), because PNS & SNS among other things contribute to LF, while PNS among other things contributes to HF (SNS doesn't). Therefore, lower LF/HF ratios are considered an indication of parasympathetic dominance. However, using this metric is controversial, since half of the variability in LF is caused by PNS & breathing is a confounding variable. [efn_note]Fred Shaffer1 and J. P. Ginsberg (2017), An Overview of Heart Rate Variability Metrics and Norms, Front Public Health[/efn_note]

Tracking meditations & naps

Oura

Meditations & naps have to be manually tracked with the "moment" feature, so you can't see which is which. You get heart rate, heart rate variability & temperature metrics.

Emfit QS

Meditation & naps can be automatically tracked (if you sit on the bed above the sensor while meditating), but both are seen as sleep periods, so you can't see which is which. You get heart rate, respiratory rate & movements metrics.

Winner: It depends...

Oura is better at tracking meditations because you don't have to sit in your bed.

Emfit QS can automatically track naps & meditations (if you sit on the bed above the sensor while meditating), but both will show up as sleep periods in the app.

The app

Oura:

The app is very intuitive and guides you more than the Emfit QS app.

For example:

  • Gives a description together with its readiness & sleep score
  • Gives your ideal bedtime
  • Tells you the reason your heart rate took too much time stabilizing might have been because you ate a meal too close to bedtime

Below is a video of me walking through the app:

Emfit QS:

The web app has a learning curve, but it's good once you get used to it!

Below is the dashboard you look at daily. It's a bit optimized towards athletes.

It has 4 charts for HRV metrics: HRV RMSSD, total recovery, integrated recovery & ANS Balance (ANS balance is LF/HF ratio, which is a frequency-domain HRV metric), which is useful if you want to see if you are approaching overtraining! (Or haven't trained hard enough)

It's also possible to see trends for all your stats:

It also has a live monitor! (Pretty cool)

Below is a video of me walking through the app (on mobile):

Winner: Oura

Oura only wins because it has less of a learning curve.

Data storage

Oura:

Storage on the device: Can store data for up to 6 weeks before syncing!

Storage in the cloud: Your data is saved until you delete your account!

Emfit QS:

Storage on the device: Only enough for 10 hours of data, which gets lost if the device doesn't get connected to Wi-fi...

Storage in the cloud: They "only" save your data for 360 days...

Winner: Oura

Integrations, API & Data export

Oura:

Integrations: Oura integrates with HRV4Training, Gyroscope, Cronometer, Heads Up Health, Samsung Health, Google Fit, Health Sync, Wattson Blue, Bioloop Sleep, FitnessSyncer, iHealth, Wattson Blue & many more.

API: Their API is free to use.

Data export: With data export as .CSV you only get 1 value per night, which might be sufficient for analyzing most things.

When downloading as JSON you can get access to HR & RMSSD (HRV) for every 5. minutes, and activity for every minute.

Meditations & naps cannot be exported.

Emfit QS:

Integrations: Emfit integrates with Trainingpeaks, Wellmo, Validic & IFTTT. With the IFTTT integration, you can trigger events for when you leave the bed, return to the bed or fall asleep.

API: Their API maybe costs a monthly fee, but I couldn't find the price.

Data export: When downloading the data you get many separate .CSV files for each night. You get access to heart rate, breathing rate, and activity for every 4 seconds, sleep stage for every 30 seconds, and RMSSD (HRV) for every 3 minutes. You also get access to timestamps for when you toss & turn or leave the bed.

Meditations & naps cannot be exported.

Winner: Oura

Oura has way more integrations, a free API & export is just 1 single file.

Emfit QS has fewer integrations, I couldn't find their API & export is multiple .CSV per night, rather than putting it all in one file.

Accuracy & comparison of data

Oura:

  • Heart rate: r2=0.996, when compared to medical-grade ECG device! [efn_note]Hannu Kinnunen, Aleksi Rantanen, Tuomas Kenttä, and Heli Koskimäki(2020), Feasible assessment of recovery and cardiovascular health: accuracy of nocturnal HR and HRV assessed via ring PPG in comparison to medical grade ECG, Institute of Physics and Engineering in Medicine[/efn_note]
  • Heart rate variability: r2=0.980, when compared to medical-grade ECG device! [efn_note]Hannu Kinnunen, Aleksi Rantanen, Tuomas Kenttä, and Heli Koskimäki(2020), Feasible assessment of recovery and cardiovascular health: accuracy of nocturnal HR and HRV assessed via ring PPG in comparison to medical grade ECG, Institute of Physics and Engineering in Medicine[/efn_note]
  • Respiratory Rate: Shown to be accurate within 1 breath per minute for the whole night, when comparing with medical-grade research tools! [efn_note]https://blog.ouraring.com/how-accurate-is-ouras-respiratory-rate/[/efn_note]
  • Total sleep time: Correlation of 0.92 with Polysomnography (the gold standard for measuring sleep)[efn_note]de Zambotti M, Rosas L, Colrain IM, Baker FC. The Sleep of the Ring: Comparison of the ŌURA Sleep Tracker Against Polysomnography. Behav Sleep Med. 2019;17(2):124-136. doi:10.1080/15402002.2017.1300587[/efn_note]
  • Sleep onset latency: Correlation of 0.53 with Polysomnography (the gold standard for measuring sleep) or Electrooculogram. [efn_note]de Zambotti M, Rosas L, Colrain IM, Baker FC. The Sleep of the Ring: Comparison of the ŌURA Sleep Tracker Against Polysomnography. Behav Sleep Med. 2019;17(2):124-136. doi:10.1080/15402002.2017.1300587[/efn_note]
  • Wake after sleep onset: Correlation of 0.58 with Polysomnography (the gold standard for measuring sleep) or Electrooculogram. [efn_note]de Zambotti M, Rosas L, Colrain IM, Baker FC. The Sleep of the Ring: Comparison of the ŌURA Sleep Tracker Against Polysomnography. Behav Sleep Med. 2019;17(2):124-136. doi:10.1080/15402002.2017.1300587[/efn_note]
  • Sleep stages: 65.7% of the time it classified the same sleep stage as Polysomnography (the gold standard for measuring sleep) in one study[efn_note]de Zambotti M, Rosas L, Colrain IM, Baker FC. The Sleep of the Ring: Comparison of the ŌURA Sleep Tracker Against Polysomnography. Behav Sleep Med. 2019;17(2):124-136. doi:10.1080/15402002.2017.1300587[/efn_note].
  • Temperature: 99.3% corerelation under lab conditions or 92% correlation under real world conditions, when compared to research-grade iButton! [efn_note]https://blog.ouraring.com/temperature-validated-accurate/[/efn_note]

Emfit QS:

  • Heart rate: r2=0.81, when compared to an ECG-based reference device.[efn_note]Ville Vesterinen, Niina Rinkinen, Ari Nummela (2019), A Contact-Free, Ballistocardiography-Based Monitoring System (Emfit QS) for Measuring Nocturnal Heart Rate and Heart Rate Variability: Validation Study, JMIR Biomedical Engineering[/efn_note]. In another study, the mean from the Emfit QS was found to be -0.8 BPM different from an ECG-based reference device [efn_note]Ville Vesterinen, Niina Rinkinen, Ari Nummela (2019), A Contact-Free, Ballistocardiography-Based Monitoring System (Emfit QS) for Measuring Nocturnal Heart Rate and Heart Rate Variability: Validation Study, JMIR Biomedical Engineering[/efn_note]. But as can be seen below, the trend is the same as the Oura ring.
  • Heart rate variability: r2=0,79 of Ln RMSSD measurements, when compared to an ECG-based reference device. [efn_note]Ville Vesterinen, Niina Rinkinen, Ari Nummela (2019), A Contact-Free, Ballistocardiography-Based Monitoring System (Emfit QS) for Measuring Nocturnal Heart Rate and Heart Rate Variability: Validation Study, JMIR Biomedical Engineering[/efn_note]. But as can be seen below, the trend is basicly the same as the Oura ring.
  • Respiration rate: 95% of measurements fall within the interval of -2.5 respiration cycles per minute (RPM) smaller or 2.2 RPM larger than those from an respiratory inductive plethysmography. [efn_note]Jukka Ranta, Timo Aittokoski, Mirja Tenhunen, and Mikko Alasaukko-oja (2019, EMFIT QS heart rate and respiration rate validation, IOP Publishing Ltd[/efn_note]

Below the data from Oura & Emfit QS will be compared

Average resting heart rate

Lowest resting heart rate

Average HRV (RMSSD)

Oura uses average HRV as a metric, but Emfit QS has seperate HRV values for morning and evening, so I just found the average of those.

Readiness (Oura) vs. HRV score (Emfit QS)

Bed time start (evening)

Sleep latecy

Bed time end (morning)

They don't agree very well. Emfit QS is very good at detecting when I'm still in my bed, while the Oura ring often thinks I'm out of my bed just because I'm awake in the bed.

Awake time

From my manual tracking it seemed like Emfit QS was better at knowing when I was awake or asleep. The oura ring always thinks I fall asleep within 10 minutes, even though it often takes 20-60 minutes. One night I know it took me at least 1 hour and 15 minutes to fall asleep because I checked the clock and oura said it took me 7 min. to fall asleep...

Total bedtime

Total sleep time

Deep sleep time

Light sleep time

Rem sleep time

Oura always detects suspiciously little REM sleep. Don't know if it's true or whether Emfit QS is more correct...

On average REM should take up 20-25% of our sleep [efn_note]Harvey R. Colten and Bruce M. Altevogt (2006), Sleep Disorders and Sleep Deprivation, National Academies Press (US)[/efn_note], which is 1.42-1.77 for me (because my Oura data says I sleep 7.09 hours on average), but on average Oura only says I get 0.93 hours REM sleep (Oura could also be the more correct one... I don't know).

Sleep score

Respiratory rate

Winner: Not sure...

  • There are more studies on Oura, and they show better results... but:
    • Almost all metrics show the same trend, with a few exceptions:
      • Awake time & sleep latency is very different. I think Emfit QS matches better with my manual tracking. (Also, the studies from Oura doesn't show high correlations with Polysomnography.)
      • The respiratory rate shows different trends, but I don't know which one is more accurate.
    • Deep sleep & REM sleep show (kind of) the same trend, but with Oura having lower REM and higher deep sleep. The REM durations from Oura are way below the average of 20-25% of total sleep time, so I think Emfit QS is the most accurate (but I could be wrong).

Summary

Oura Emfit QS
Convenience Loser!

You have to take it on and off & charge it
Winner!

You only have to set it up once (if you don't travel)
Traveling Winner!

Weekend traips: Just bring the ring with you
Longer trips: Just bring the ring & charger with you
Loser!

Every trip: Set it up & connect it to wifi (4-10 minutes).
The box takes up 5 times more space!
Available metrics No clear winner!

Heart rate, Heart rate variability (RMSSD), Time in bed & time asleep, Sleep stage (Deep, light, REM & awake), Respiratory rate.

Continuous activity score, Body temperature
& Steps
No clear winner!

Heart rate, Heart rate variability (RMSSD), Time in bed & time asleep, Sleep stage (Deep, light, REM & awake), Respiratory rate.

Continuous activity score (only in the nighttime), Toss, turn and bed exits & Autonomic nervous system balance (LF/HF ratio)
The app Winner!

More intuitive
Loser!

It has a learning curve
(But the live monitor is cool)
Data storage Winner!

Device: 6 weeks storage.
Cloud: Forever (until you delete your account)
Loser!

Device: Only 10 hours...
Cloud: "Only" 360 days...
Integrations, API & Data export Winner!

More integrations, free API & 1 simple .CSV file when exporting
Loser!

Fewer integrations, couldn't find their API & multiple .CSV files per night when exporting
Accuracy & comparison of data No clear winner!

Oura has more validations studies with better results, but were not good at detecting when I feel asleep & woke up.
No clear winner!

Fewer validation studies, but most of the data was similar to Oura, except the data about when I fell asleep & woke up which was more accurate (according to my manual tracking)

Summary of summary

Oura:

  • Less convenient for everyday use, but more convenient when traveling
  • Only the Oura has these metrics: Continuous activity score during the day, body temperature & Steps
  • More intuitive user interface
  • Can store your data "forever" in the cloud & on the device for 6 weeks without syncing!
  • More integrations, free API & simple .CSV export

Emfit QS

  • More convenient for everyday use, but less convenient for traveling
  • Only the Emfit QS has these metrics: Toss, turn and bed exits & Autonomic nervous system balance (LF/HF ratio)
  • The app has a learning curve (but with a cool live monitor)
  • Can only store 10 hours of data on the device & 360 days in the cloud
  • Less integration, couldn't find their API & .CSV export is inconvenient.

My choice

I was very tempted to buy the Oura ring since it is convenient when traveling! But I ended up choosing the Emfit QS despite it losing 1-4 to Oura..

The Oura app is more intuitive, but I have already gone through the learning curve of the Emfit QS user interface, so that doesn't matter for me.

The Emfit QS only has 10 hours of data storage, but as long as my Wifi doesn't suddenly stop working without me noticing (pretty unlikely), then it syncs automatically anyway (I can use my smartphone hotspot as a backup). They only store my data for 360 days, but I plan to do quarterly backups in Google Sheets or similar.

Emfit QS also has less integrations, but I didn't plan to use any of the integrations anyway. I'm more interested in exploring the data myself.

The thing that really made the choice:
I want to make my tracking setup as passive as possible!
Emfit QS is more convenient for everyday use, while Oura is more convenient when traveling, and I plan to spend more time not traveling than traveling (I can still bring it with me as long as there is Wi-fi & an outlet).

4 Likes