The Fitbit software makes an interesting attempt to measure ‘sleep effectiveness’.  When you go to sleep, you put the device into sleep mode by pushing and holding the button.  At that point it starts measuring your ‘micro-movements’ to determine how restful your sleep is.  The idea is that the less movement you have during the night, the better your sleep is.   There is actually some science behind this (called actigraphy), and it must be legitimate because it has a Wikipedia page.

Anyway, the Fitbit web site reports your sleep as a chart.  Here is a typical one for me:


The baseline blue bar is hardcore sleep-time, no movements.  The vertical red lines occur when a movement is detected.  Getting out of bed or a very sharp movement would result in a larger line.

Looks like I have a nice, long period of absolute inaction, with only a few movements during the night.  Saying I had 8 ‘Times Awakened’ is a bit of a stretch – I usually sleep pretty well and pretty hard.

They try and sum all of this up in to a 96% Sleep Efficiency.  I have no idea what that means, but it sounds good.

Just for kicks, I put the Fitbit on each of my kids for one night.  Here is my 5 year old’s chart:

I know that she is a wiggly sleeper, so I am not surprised that she had 22 times awakened.  It takes her longer to fall asleep than me, and she doesnt have any of those long periods of dead-cold slumber.

Here is the 9 year old:

This particular night she woke up in the middle of the night due to a nightmare about a bug.  The bigger line around 1:30am is her coming into our room  and climbing into our bed.  Looks like she got back to sleep pretty quickly!   Despite this, she has some good periods of hard sleep, and her sleep efficiency was better than mine!

Dont know really how useful this is, but it will be interesting to track trends as the year goes on.  I dont really have sleep problems, but if I did, I think this might be a useful way to track how effective different treatments might be.

Actually, most useful for me might be the ability to track my bedtime and overall sleep duration, which fluctuates with how busy I am at work and other factors which might change during the year.

Anyway, for those who do have sleep issues, there lots of new tracking devices, including specialized watches and brain wave reading head bands to wear while you sleep.   I think learning about my sleep cycles and REM sleep would be fascinating.   For those that dont want to wear a device, there are even iPhone apps that you put under your pillow  to track your movements that seem to work surprisingly well.

Leave a note below if you have any more experience with these trackers.  thanks!

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