I have been running off-and-on for the last 3 years (mostly off) and running regularly for the past 15 months. I love how lightweight it is the antithesis of biking or backcountry hiking with their emphasis on gear. Running is nearly completely free of equipment and gear. All I do is strap on my shoes, plug in the headphones and go. The exception to this is my Nike+ iPod pedometer. This is a cool gadget that consists of a sensor which goes in your shoe and a receiver which plugs into the 30-pin connector on the bottom of the iPod Nano. If you use an iPod Touch you don't even need the receiver.I was blown away by the accuracy of the device and have been rediculously satisfied with this $30 gadget. Two events brought home how accurate the pedometer was: I ran a Cinco de Mayo 5k in Brooklyn with my sister a few years ago. The pedometer signaled 5k on the very footfall that crossed the line finishline. It was accurate to the step. Amazing:
I had a similar experience in the Detroit Marathon Relay in 2007. I ran a short segment from Downtown to Belle Isle. As soon as I crossed the timing blocks the iPod signaled I had reached my goal:
Last fall when I did the half marathon the accuracy fell a bit. It recorded 13.6 for a 13.1 mile route but I felt that 5% slosh was okay:
I had the same over estimate occur during the martian Marathon 10k. With the devic recording 6.5 miles for a 6.2 mile run. Again a 5% error:
What inspired this post was the new finding that in 2009 the error has swung in the opposite direction, now the Nike+ is underestimating my distance and speed. I first noted this during an 8.5 mile loop I ran with PBFluids reader and fellow nephrologist Steve Rankin. The Nike+ only recorded 7.98 miles:Yesterday I did the Dexter-Ann Arbor half marathon and again the Nike+ iPod underestimated the distance and speed:
In the end it was only off by 0.6 miles over 13.1, so 5% but on my next run my Nike+ odometer will cross 1000 miles and its a little less satisfying thinking that I already crossed that milestone at some unrecognized time in the last month or so.
Update: Just discovered that the New York Times recently did a review of the Nike+iPod system.
