What is the point of the Sleep Score?

[Appin]

So, every morning, I get up and I sync my Ionic and I check my sleep score for the previous night. It's almost like an addiction! It can vary from low 70's to high 80's and the charts look really cool. Trouble is, it bears absolutely no relation to how I feel in the morning! A high score does not mean refreshed and feeling energetic and sometimes with a low score I feel great! So I am left asking myself the question, what is the point of the sleep score? 

[gymaddict20]

i think the point of sleep score is to analyze all the different sleep patterns you have, ive been reading about my own sleepscore and it uses word such as REM and light sleep, restless which is super interesting because i believe that if you sleep more then 8 hours you have a pretty good chance of losing weight so use it to analyze your sleep patterns and see where you can improve 

[Appin]

Hi, thanks for your input. I absolutely agree that the breakdown of REM, Deep, Light sleep etc is interesting but the point that I was trying to make is that the actual score doesn't seem to match up the reality of the quality and effectiveness of sleep and is therefore more or less meaningless. I have also never read anything that validates the idea that sleeping more than 8 hours helps weight loss sadly. That would be brilliant! I could stay in bed all day long and stop being such a big fat lump!

[gymaddict20]

i think you can find articles about how sleep affects weight loss if you search for it however you need to keep in mind that weight loss is like 90% of what you eat and 10% exercise 

[adebaser]

As far as I'm concerned the sleep score is nonsense. Look at this example:

How can it be that Wednesday got a 68, only 6 less than Tuesday? I felt so bad the entire day. I was cognitively impaired. I couldn't remember what I was doing at work, I kept zoning out and found it difficult to concentrate, my eyes were sore and itchy and heavy. But according to Fitbit it wasn't too bad!

How does it work that out? I fell asleep at 4am, got only 24 minutes of deep sleep. On Tuesday I had 2 hours of deep sleep, and almost double the amount of total sleep. How can the scores be so close? It's useless as an indicator of anything.

Edit: also I wonder what you would have to do to get 100. Is it even possible? I've never seen above 86 since they introduced sleep scores. And what would one have to do to get below 50 or 30? My lowest is 65. If you get less than 3 hours then it doesn't track it. So is it not really a scale from 0-100 at all?

[gymaddict20]

Today i got a sleep score of 91. i went to bed last night at 0:55 and woke up at 12:26 so i basically slept 10 hours and 19 minutes. if i would have slept an hour more i probably would have gotten a 100 sleep score 

[rockpool]

Gymaddict20, I hardly believe sleeping longer would have automatically given you a higher score.

This morning I had more deep sleep than since the scores started and more REM sleep than for a long time, awake percentage was about as usual. But the sleep score was only 70. (my average is 75), The only thing I can see that was different last night is that I spent more time than usual in bed (more than 9 hours) and got more sleep than ever (8 hours 20 minutes, whereas I set my goal to 7,5 hours and usually get less than that).

I would very much appreciate if Fitbit could explain how they weigh the various results to calculate the score. It doesn't seem at all logical to me. Today I feel more rested than for a very long time, yet got a lower score than usual.

[gymaddict20]

Maybe you are right, if I slept longer then I still could have gotten the same sleep score. I am sure that if you contact Fitbit they can give you a breakdown of how it works! keep me in the loop because I am curious to hear what they have to say 

[adebaser]

I managed to get a new record low sleep score - by sleeping for 10 hours. So it certainly seems that it considers sleeping too long far worse than not sleeping enough, even though how you feel the next day will be pretty much the opposite.

[Colinm39]

I have found as I lower my RHR my score in the Premium Restoration plummets resulting in a lower sleepy score.  Even though it's only 25% of the total sleep score I lost 10 points out of 25 the other night.  That's because my sleeping average HR is nearly the same as my RHR.

My average sleeping HR was 54 and my RHR was 55.. and 53% of my HR was below the line..

Another example I only lost 5 points. My average sleeping HR was 55 and my RHR was 58 and 80% was under my RHR line..

I have a slow HR normally and passed by the specialists...

[Dominique]

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@gymaddict20 wrote:

Today i got a sleep score of 91. i went to bed last night at 0:55 and woke up at 12:26 so i basically slept 10 hours and 19 minutes. if i would have slept an hour more i probably would have gotten a 100 sleep score 

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@gymaddict20 : incidentally, my best sleep score so far is also 91. Since you were asking about the breakdown, here it is (for my own sleep rated 91, your breakdown is likely different):

"Time asleep" accounts for 50% of the total, the remaining 50% being evenly split between " Deep and REM" and "Restoration". 46 + 23 + 22 = 91.

To answer your question about reaching a score of 100: very unlikely IMO. You would have to score 50/50 on "Time asleep" and 25/25 on "Deep and REM" and 25/25 on "Restoration". I’ve never reached the maximum on even a single component. Getting 25/25 on restoration would probably require sleeping HR to be nearly 100% below RHR and hardly any restlessness. I think the best I’ve had on restoration is 23/25.

[Dominique]

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@adebaser wrote:

I managed to get a new record low sleep score - by sleeping for 10 hours.

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The score is not directly proportional to time asleep. Here is an illustration of this. Here, I slept for 7h45m and got a score of 83:

Here, I slept for 6h39m (i.e. more than one hour less), yet I got a slightly higher score of 84:

Why is that? Well, the explanation is found in the breakdown. This is the breakdown of the longer sleep rated 83:

 Here is the breakdown of the shorter sleep rated 84:

I got a lower partial score for the shorter night (42 vs. 46), as one would expect. However, I got a far better restoration score on the shorter night, for spending 94% of the time below RHR, vs. only 48% during the longer night.

What I don’t quite understand is why I got the same partial score of 20 for "Deep and REM" in both cases, in spite of having nearly twice as much deep sleep during the longer night.

Regardless, I find the sleep scores make sense overall, when you look at the breakdowns.