Tuesday, December 31 2013

Fitbit Force

My health has been… peculiar for the last several months, and it’s quite frustrating to be repeatedly told that the latest round of tests came back negative. Generally good, since it means that the most comprehensive physical I’ve ever had says that the major systems are working perfectly, but it means that we still didn’t know what’s causing the problem that’s left me horribly short of breath and both physically and mentally fatigued.

When we finally got around to the sleep clinic, the take-home sleep study came back “inconclusive” after two weeks, and they scheduled an in-lab study two weeks later, with results coming two weeks after that.

Several of my friends have been Fitbit fans for quite a while, so while this was going on, I pre-ordered the new Force model, which in addition to steps and stairs, tracks sleep time and disruptions (based on movement during the night). It also has “social” features like auto-shaming, which I will never be taking advantage of.


Physically, it’s a lightweight watch with a one-piece silicone band. Pretty comfortable, and easy to wear all day without noticing. My only two complaints are that it it’s shaped so it can’t be worn with the face on the inside of the wrist (which would be much easier to read on exercise machines), and the clasp closes the wrong way, so that it can catch against jacket or pants as you’re moving around. I haven’t dropped it into a urinal yet (and plan not to!), but I did manage to open the clasp while filling the car up with gas one day.

Since it’s a wrist-based device, steps only count if your arms are moving, so it’s not good when pushing shopping carts or carrying things. It also has an odd definition of activity, where vigorously swinging a sword while moving around doesn’t count as more than a casual stroll. There’s actually some fairly fine-grained data being recorded, but you can’t access it without buying a premium membership for $50/year.

Stair-climbing is unreliable in two ways. First, because changes in the altimeter are ignored unless your arms are moving (to detect elevators), so again, it doesn’t work if you have your hands full or are using the handrail. Second, and likely to get fixed in an update at some point, because the altimeter drifts out of calibration over time, until it suddenly decides that my two-story house is a five-story. Once you track down the instructions on how to reboot the device, it goes back to normal, fortunately.

Sleep-tracking turns out to be the killer app for me, and paid for the device. Because when the second sleep study came back, the results were just “mild sleep apnea”, not nearly enough to account for my symptoms. A month of data showing that I only get about 3-5 hours of actual sleep a night, with frequent interruptions, gave the doctor more to work with. (he was also quite impressed with the night where I took Ambien at midnight, stayed up reading until 6am, and then was wide awake again by 10am)

It means waiting yet another several weeks to get a CPAP, and meanwhile visiting yet another specialist (gastroenterology; collect the whole set!) to find out if the sleep doc has guessed the underlying cause correctly. But without the Fitbit, we’d still be guessing, and probably scheduling a multi-night in-lab sleep study.