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Fitbit tracker's sleep tracking accuracy has been subjected to much debate, but after careful examination of facts, it is safe to conclude that Sleep Score assigned by Fitbit is neither accurate nor bear weight for further inspection.
Fitbit & Sleep Tracking
Apart from the old clipper era of Fitbit trackers which are not even in cycle now, almost every new generation Fitbit is able to track sleep. For sure, there is one big difference between the way Fitbits used to track sleep before than now, the statement stands for itself. Sleep Tracking is not new to the Fitbit. Nor is the concern of how it affects a general person.
“We are researching ways in which Fitbit can help assess conditions such as cardiovascular disease, sleep problems, stress, pre-diabetes and diabetes, and help users with interventions for chronic conditions.”
Fitbit Lead Research Scientist Conor Heneghan
When asked about the Fitbit’s greater vision this is what the lead scientist Conor Heneghan had to say. But this is not taken from yesterday, it has been a while. Meaning that Fitbit should’ve reached the primal status by now. Or at least a place where accuracy shouldn’t be questioned.
How Fitbit Tracks Your Sleep?
I wouldn’t go into the details here. We have covered the working of Fitbit Sleep Mode in details here. If you want to, you can see it for yourself. However, just for the sake of argument right now, you should know this:
Fitbit tracks sleep using two sensors, the first is accelerometer which gives your tracker information regarding your motion. Second is the PPG method deployed using greenlight which is employed to find the heart rate of a person.
In theory it feels very simple and believe me even in practice it is, and it is one of the elegant thing about it: Simplicity. But does that simplicity translates into accuracy?
Spoiler Alert: It doesn’t.
But Is Fitbit Sleep Score Accurate
The sleep score that you see on your Fitbit tracker is not what it seems to present itself. Over the years many researches have spent thousands of hours in lab testing new Fitbit models against the clinical medical equipment and every time a same theme has been painted on results: Fluctuations Within Fitbit’s Sleep Tracking Model.
Which is not a surprise. Fitbit presents to you Sleeping Stages using just two sensors like we have discussed above. When in reality or in the Lab in order to accurately tell the correct stages, brain waves are measured, which a Fitbit tracker can never do.
So if you are question was just: Is Fitbit Sleep Tracking Accurate? You have your answer. If it wasn’t please keep reading!
Issue With Inaccurate Results From Fitbit Sleep Tracking
So, there was this study with 42 people conducted at Monash University who also had trouble sleeping. It was designed to check their sleep in one night using the Fitbit and the actigraph. However, they also used a more complicated test called polysomnography. This test checks lots of things while you sleep, like what your brain is doing, how your eyes move, how your muscles work, and your heart rhythm.
The researchers found that the Fitbit was pretty similar to the actigraph in many ways. But when they compared the Fitbit to the polysomnography results, they saw some big differences. The Fitbit often didn’t catch as much deep sleep and rapid eye movement (REM) sleep as the polysomnography did. It missed about half of the deep sleep and around a third of the REM sleep. On the other hand, the Fitbit sometimes thought people were in light sleep when they weren’t actually.
Factors That Affects Fitbit Sleep Tracking Accuracy?
By now we have established the fact that Fitbit’s sleep tracking model is not accurate and you shouldn’t depend on it with your life. However, there is still some thing we need to know: What are those factors that makes the Fitbit model moot and if there is a chance we can play God here and use it for our good.
Your Motion
A very important part of Fitbit’s sleep tracking is how well it can tell you are in motion or not. Because the basic principal states that if your Fitbit will feel you are not in motion, then it will declare you asleep. Then it doesn’t matter if your reason of non-motion is because you are reading a book very quietly or you are actually sleeping.
Your Heart
Another factor which plays huge role is your heart rate. Fitbit uses both the movement and HRV (Heart Rate Variability) to decide which phase you are currently in. But here is the catch: Just like sleep tracking even heart rate monitoring on Fitbit trackers is not 100% accurate. Meaning it could be wrong about your sleep and heart rate and still be very very confident about it.
Your Fitbit Tracker
We are moving towards the year 2024 which means it’s just matter of time till we hear about the next Fitbit Versa 5 and Fitbit Sense 3. Which also means that the current generation of Fitbit devices will be more closer to end of their cycle than before. However, even more important thing is that there will be difference between the quality of the latest generation to the previous one. So if by chance you’ll be on the Fitbit device released long ago, fully expect the disparity between results.
Your Fitbit’s OS Version
A lot of your Fitbit problems can be solved with a simple solution of just updating the OS of your Fitbit smartwatch. Before you think about it, yes we are aware off how – not good – it is but believe me when I say this: that just updating the OS can save you from 75% of the problems.
Your Memory To Open Sleep Mode:
If you want to maximize the efficiency of your Fitbit tracker it is vital that it is put into sleep mode before you hit the bed. Not only would it stop notifications from distracting you, but make sure your Fitbit tracker can give it’s best – even if it’s not actually the best.
Note: Confused about the Sleep Mode icon? Head to our guide on Fitbit Symbols and learn to recongize it.
Your Surrounding
As we mentioned in first factor. Fitbit takes the movement of your body and use it extensively to give you a score. So if you are sleeping beside a pet or partner even if you won’t their abrupt movement can lead your Fitbit to a rabbit hole it might never get out off.
Tips To Improve Accuracy Of Fitbit Sleep Mode!
Taking into account the method Fitbit has implemented to track your Sleep, it’s difficult to give sure fire tips. Following few can help to turn around the leaf:
- Always make sure to at least have slept 3 hours before checking the record.
- As Fitbit uses heart rate sensor it is vital for optimal monitoring to have sufficient contact between your arm and the tracker. Keep it intact and close.
- For comfortability you can always switch the tracker to your non-dominant arm. Reports show little to no change in reading when done so.
In happenstance your Fitbit tracker stops reading your sleep records, dive deeper into the problem. However, it might seem there is always a ways to turn things around, and yes it includes Fitbit too.
Frequently Asked Questions
It is estimated that Fitbit trackers are only 60% accurate in context of Sleep Tracking.
Not 100% that is for sure.
Just enough to not pay much heed towards their finding. If your tracker is telling you something is wrong, contact doctor before making any rash decision.
There is no one way. You can try methods like staying in bed for at least 3 hours and staying still but apart from it, there isn’t much you can do to convince your Fitbit to show you went to Deep Sleep even when you actually did it.
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