Sleep tracker accuracy

[Laurennicole87]

I was wondering how accurate the flex sleep tracker is. I know I don't sleep well, but I am normally getting 5 hrs of sleep or less. I go to bed between 10 and 11 and don't get up until 7:30. Is the accuracy off or am I really not sleeping that well at night?

[SunsetRunner · Accepted solution]

Hi @Laurennicole87

Moved this thread from the Flex to the Improve your Zzzs section since believe it will get more attention here.

[Marcy]

I can't speak for the Flex, but I in my opinion the sleep feature works well if you use it to spot trends in your sleep habits rather than worry too much about the total sleep hours of a specific night. From what I recall, the total sleep hours does not include restless time, yet you may be sleeping/dozing. My sleep hours are sometimes inflated when I read in bed.

[CallieM]

@Laurennicole87 welcome to the Fitbit Discussion boards 🙂

If you feel like the settings on your Flex are too sensititve to movement, your sleep settings may be set on "Sensitive" instead of "Normal" (Normal is appropriate for most users).

To change your setting in the Fitbit iOS app, go to Account > Advanced Settings > Sleep Sensitivity. To change your setting in the fitbit.com dashboard, go to Settings > Devices > scroll down to Sleep Tracking.

Thanks @Marcy for your input. As a side note, if your tracker is picking up sleep time while you're reading before bed, you can edit your sleep log to note when you stopped reading, and went to sleep. Check out this article about how to edit a sleep log!

I hope this helps the both of you - let me know how it goes!

[nohypochondria]

If it's set on normal , you will have great sleep patterns of a healthy person. Set on sensitive, you will look like an insomniac that needs medical help. The same is true for the activity trsacking. If I mow my lawn, the vibration from the mower makes it look like I walked 12 miles. readings from this need to be taken with a grain of salt. People get obcessed with the data , but , need to keep a level of common sense. 

[CobaltStargazer]

@nohypochondria: yes indeed I see this happening in my results too. I have tried both Normal and Sensitive modes and your observation is true for me too.  Surely this means the Charge HR tracker is completely invalid as an even half-reasonable measurer of sleep?

• If so I want my money back.

• If not then please - how do I use it to get sensible measurements?

[Laurennicole87]

I already have it set to normal. I was just wondering how accurate it is.

[CallieM]

@nohypochondria thanks for your input. Please keep in mind the differences between Normal and Sensitive settings:

• The normal setting counts significant movements as being awake (such as rolling over) and is appropriate for most users.
• The sensitive setting will cause your tracker to record nearly all movements as time spent awake. This setting may be helpful for users with sleep disorders, or those who wear their tracker somewhere other than the wrist while asleep.

Learn more here!

@Laurennicole87 please double check to make sure your Sleep Tracking is set on Normal. It seems very likely that your settings are set to Sensitive. 

To change from Sensitive to Normal, follow these steps:

1. Login to your account at Fitbit.com

2. Click Settings in the top right corner (the gear icon)

3. Click on 'Settings' from the drop-down menu. 

4. In the left column, click on Devices

5. Click on your tracker type (Surge, Charge HR, Blaze, etc)

6. Scroll down to Sleep Tracking

7. Switch from Sensitive to Normal

8. Make sure you save and sync so that the changes are applied to your account

I've included a screenshot of the area where Sleep Tracking settings are located on your fitbit.com profile.

You'll notice the last row, titled Sleep Tracking. 

I hope this helps - learn a bit more about how to change from Sensitive to Normal in this Help article. 

Let me know how it goes or if you have any questions!

[Cheryl06]

I am also wondering how accurate the sleep tracking is?  It says I get an average of 4 hours a night, but I go to bed at 10:00 om and I am up between 5:30 am to 6:00 am. I could see 5 1/2 to 6 hours, but 4??

[rgravesx2]

Hi.. I've had my flex for over a week and so far, love it. However, I wasn't sure of how often to charge it and it lost charge during sleep last night. 😕 Mine does track restlessness and time awake, however after losing charge it didn't track that part, but the still the hours in bed. Strange. Lesson learned though, stay on top of it charging. 😉

[shipo]

I wonder if anybody has transitioned from a tracker like the Flex to one of the trackers with a heart rate monitor (Charge HR, Blaze, Surge).  I really like the sleep tracking feature of my surge (I have severe sleep apnea and use a CPAP) coupled with the sleeping heart rate plot.  The two plots (sleep and heart rate) complement each other when there is gross movement (rolling over or paying a visit to the bathroom), but the HRM shows other transients such as how deep my sleeping state is as well as what I assume to be dream segments.

So, if any of y'all have made the transition from non-tracked heart rate to a tracker with the HRM feature, what is your impression?

[CallieM]

@Cheryl06 hmm, that does sound pretty low. Did you recently change your settings from Sensitive to Normal? If so, this could be bringing down your average. Please also ensure that your trackers firmware is up to date. You might also try a restart, if you haven't already. Restart instructions are here!

@rgravesx2 thanks for reaching out to our Community! On your Fitbit app, you should be able to see the battery life of your tracker. I've included a screenshot so that you can reference where the battery indicator is located. If you look in the top left corner of your app, you'll see that there's a little icon of whichever tracker is paired, with a battery symbol next to it. In my case, the battery is low so the battery turned red. If you have the old iOS dashboard or an Android device, this will look a bit different. Let me know which type of phone you have so that I can be more specific! 🙂

[CobaltStargazer]

regarding Sleep Tracking accuracy, a couple of people have responded to my question about the validity of the Charge HR in thois area by suggesting that ' the Fitbit will overr time work out the accurate sleep recording'.

I am sorry but I just don't see how that is possible! Unless the Fitbit is blessed with some advanced Artificial Intelligence and is able to track alteration in brain waves, then it surely must just rely on two basic measurements  - movement detection and heartrate. Well, I can and often do lie in bed motionless and wide awake for long durations. I also can do the same late night on my sofa whilst watching TV. It thinks I am asleep but I am not. Therefore I am tempted to say that, relatively speaking, its a "dumb machine" as I can see no scientific way that it can possibly track sleep without giving the broadest 'measurement' based on movement and heartrate.

I would genuinely be pleased if anyone here can supply evidence of the algorithm or process which underpins the sleep tracking function so that I can once agin be confident that it is worth using.

[shipo]

After observing the various graphs and plots which are generated by my Fitbit Surge, I must say, even without an uber cool brain scan, the sleep data provided looks to be pretty darn accurate.  True, the Surge has no way of identifying REM sleep, but beyond that, it is spot on when using it to determine sleep efficiency.  Consider the following (two shots from the same day):

Heart rate plot (five minute average):

Sleeping plot:

To my eye at least, the periods of longest/deepest sleep correlate to the lowest heart rate while periods of restlessness (rolling over, getting up for a drink or to visit the bathroom...) map pretty nicely to small spikes in my heart rate.  Given I have pretty severe sleep apnea (controlled with a CPAP), the sleep tracking of my Surge is both an accurate and necessary tool for me.

[CobaltStargazer]

@shipo Interesting to read your comments. Thanks for adding them  - and the pics. Really glad its working for you as a measure. I might have that Apnea thing too but have no CPAP. This is why I wanted the FitBit in the first place - to see if I need an Apnea assessment - to go to the Physician with some data about my sleep patterns.

I cannot see from your screen-grabs though how your recorded heart rate coincides with your recorded Sleep restlessness periods as the former is showing against a Morning-to-Evening timescale and the latter is showing against just an overnight timescale. Maybe you have other screens you can see which shows the direct comparison along the same timescales?  I have to use the Windows PC Website version of the 'tools' so it looks different to your App in any case.

For me the issue is about getting an objective external reference measure to compare the FitBit data with, and I am not sure how to do that, other than going to a hospital and being hooked up to proper medically accurate sleep measuring equipment - and I think that is rather unlikely to be available to me.For me it is not valid enough just to use the FitBit version of data and to subjectively sense that it is right. I am wondering if FitBIt can make available their Valiidity and Reliability data for this function, and to tell us how they verified that. I think I may ask them soon enough.

[CobaltStargazer]

I spent a while on the FitBit online Chat help facility tonight with a request to see the validity and reliability (extrernal benchmarking for accuracy) data for the FitBit sleep measurement function. Despite having a very helpful and patient Customer Service Helper, they did not have access to such data. I may lodge a request for the same data via email tomorrow to see if I can see it.

[GDabney]

I don't know what I did, but I was trying to enter start and stop times in my sleep log, a message came up asking if I wanted to delete my sleep log. It gave the option to cancel or delete. I clicked cancel but now when I go to my Dashboard the sleep tracking information isn't there. How do I get it back?

[CobaltStargazer]

I have a question which illustrates the underlying issue in my previous post about FitBit Sleep tracking measurement which I am trying to resolve, and I want to use a diagram to try to explain it:  Looking at the picture below, which shows two 6 inch rulers, what is the length of the blue rectangle?

[GDabney]

The top ruler shows a measurement of 3 inches but the bottom one shows a measurement of 2 & 1/2 inches

[shipo]

@CobaltStargazer, is this an IQ test?  😛