Brad Feld

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More On Human Instrumentation Around Sleep Data

Dec 15, 2009
Category Technology

I’ve introduced two new devices into my personal human instrumentation experiment.  In addition to my Zeo, I am now carrying around a FitBit and using a Withings scale.  I’ve discovered the mild embarrassment associated with having a scale mis-tweet your weight by 10 pounds too much (e.g. “Brad – you gained a lot of weight recently – everything ok?”)  But I suppose that is part of the experiment.

The comparison on the Zeo and FitBit sleep data is fascinating.  Take a look.  Zeo from last night first.


Now the FitBit from last night.


The Zeo breaks things down into four categories: Wake, REM, Deep Sleep, and Light Sleep.  The FitBit only has two: Active and Asleep.  My FitBit time setting is wrong (it has me going to sleep at 9:17 but I went to bed at 11:10 – I’ll need to figure out how to fix that).  But both have me in bed for a little over 9 hours, although the FitBit thinks I was only asleep for 8:17 of it.  The Zeo has me asleep for 97% of the time; the FitBit has me at a Sleep Efficiency of 95%.

I need a few more nights of comparative data to completely understand the differences, but I thought I’d toss up a baseline to get started.    Oh – and I slept in this morning – I felt kind of crummy and decided to just sleep to try to shake off whatever was creeping up on me.