Fitbit Versa 3 Incorrectly Reporting REM Sleep

[DevonC]

Hello:

I have a problem with my Fitbit Versa 3. It is not accurately reporting the amount of REM sleep I get. I have a condition called sleep paralysis. Because of this, I went for a medical sleep study. It showed that I was in REM sleep for 25% of the night. My Fitbit app has never said that I get anywhere near that. It typically shows somewhere between 5-7% of my sleep in REM. I know for a fact this is inaccurate, especially since when I do have sleep paralysis, it should show me as in REM and then waking. It often shows me as in Light Sleep and then waking, which isn't possible, since sleep paralysis only occurs during REM sleep.

I am a a male, 172 cm tall, and weigh 71 kg. My resting heart rate usually falls at 55bpm, which I think is oddly low. I have speculated as to whether my heart rate doesn't elevate as much as most peoples does during REM sleep, and if this is why the Fitbit is not tracking it.

In short: I know that I spend a lot more time in  REM sleep than my Fitbit tracker reports, but, I don't know whether it's a flaw with the product or something to do with my heart rate, but any help or insight would be greatly appreciated.

[LZeeW]

@DevonC   A medical sleep study usually includes EEG monitoring.  An EEG is the most accurate form of sleep analysis.  Fitbit uses a combination of your lack of movement and heart rate variability to estimate your sleep stages.  Help article  Please keep in mind that Fitbit's sleep stages are estimates.  One person's flaw in technology is another person's limitation of technology.  Fitbit has a good reputation when it comes to sleep analysis.

I have seen posts from other users with other sleep disorder diagnoses.  They were looking for insight, too.  Your Fitbit is not a medical device.  It is technology with limitations.