Detailed Sleep Data and Breathing Rate, HRV and SpO2 Heart Metrics

[Bill_209]

My Inspire 3 device returns these data reliably, but I've had to return three of my wife's devices that never returned these data and the CS team was unable to resolve this issue in all 3 cases.

Unfortunately, the latest device FW and app SW updates didn't resolve the missing data issue on my wife's devices, so I am hesitant to purchase her a fourth device until a FW and/or SW 'fix' for this product performance issue is in place to resolve it.

Is there a device FW or app SW update on the horizon that will hopefully resolve this missing data issue that only seems to affect some Inspire 3 devices?

[Julia_G · Accepted solution]

Hi, @Bill_209 , have you tried letting your wife wear your Inspire 3 for a night or two to see if it gives expected data when she wears it?  That would help identify whether it is the Fitbit or instead something about your wife’s interaction with the device (for example, these data are based on being able to consistently detect heart rate - it may be that for some reason it is difficult to detect her HR).  If your device gives her the expected data then you can confirm whether or not it is the individual device.

Just a thought… 

[Bill_209]

No, we didn't try doing that, but we tried the recommended things like experimenting with different band tightnesses, normal and sensitive settings and wearing the device on the dominant and non-dominant hands.  In all cases, the HR curve was normal looking and unbroken, but the devices only returned basic sleep data and no Breathing Rate, HRV and SpO2 data.  Very strange.

[Bill_209]

Excellent troubleshooting idea, however, so I just put my known-good device on my wife's wrist and we'll see what happens when she wears my device for at least 3 days.

[Bill_209]

This experiment of putting my known-good Inspire 3 device on my wife's wrist Friday afternoon has been interesting, to say the least. My device is now behaving exactly the same as her devices that we returned for not working properly, so something is definitely going on here.

On Saturday morning, the device only returned basic sleep data and no Breathing Rate or HRV heart metrics, but her SpO2 was 94%, so at least that was good. However, her HR curve showed one 41 BPM event during the night, so it's time for my wife to call her doctor on Monday morning.

On Sunday morning, she also only got basic sleep data and no Breathing Rate or HRV heart metrics, with a 94% SpO2, but the Today HR curve is totally missing on the app.  However, the HR is being updated and it shows a range of 42 - 106 BPM when it is out of range from the phone, so she definitely had another low BPM event last night as well.

Does anyone know what would prevent the Today HR curve from appearing on the app?  I can't find the HR curves on the Fitbit online dashboard, but maybe I just don't know where they are.

[Bill_209]

I found the missing app HR curves on the Fitbit online dashboard and they are continuous, so that doesn't explain why my wife isn't getting detailed sleep data or why the HR curves are missing on the app.  Clearly a sync issue/bug there that will hopefully be resolved soon.

I've also been reading a bit of the Fitbit SDK documentation and it states that a minimum of 3 hours of uninterrupted sleep is required to get detailed sleep data, as well as the Breathing Rate, HRV and SpO2 heart metrics.  Additionally, Breating Rate and HRV data will not be returned unless there is detailed sleep data.  That helps to explain why my wife gets Sp02 data, but no Breathing Rate or HRV data.

So, it appears that people that don't have a restful nights sleep by Fitbit's criteria will rarely, or never get detailed sleep data or Breathing Rate and HRV heart metrics, which is unfortunate, because that's why we purchased our Inspire 3 devices to obtain.

Hopefully, Google/Fitbit will improve their sleep algorithms to make their fitness devices more robust and useful for those of us that are interested in using them to track sleep and heart metrics.

[Bill_209]

My wife actually got detailed sleep results last night and the 'Today' Heart Rate curve is showing up on the app this morning.  Still no HRV data, but the Breathing Rate heart metric is there.

Her lowest HR value last night was 55 bpm, so maybe Fitbit doesn't return detailed sleep results or heart metrics, and possibly the HR curve, if there is a HR measurement in the low 40s overnight?

In any case, my wife's doctor has referred her to a cardiologist for testing for possible Bradycardia so, if anyone isn't getting detailed sleep results and Breathing Rate and HRV heart metrics, take a look at your HR curve to see if there are any HR measurements below 50 bpm.  There appears to be a correlation there, but I have no way of knowing that for sure.