So, I finally broke down and calibrated my Nike+ after a year of running with it. I knew that it was a little off, because it always told me my runs were a little farther than I actually thought. After calibratign it, I found out that it’s been telling me that I was going 1.2 miles for every 1 mile I actually ran.
The fact that the distance has been off doesn’t bother me nearly as much as the pace factor. I’ve never run very fast (I guess it’s more of a “jog” than a “run,” if you want to get technical), but now I’m realizing that I’m much slower than I originally thought.
I’m not really running for speed so much as distance – I’ll be happy just to finish the marathon, even if it takes half a day to do it – but I was really feeling good about my pace previously. With the Franklin Classic 10K coming up next weekend, my pride has taken a little bit of a hit. But I guess it’s better to realize I’m slower than I thought now than on race day…
I calibrated my nike+ kit once and didn’t notice much difference in how it reported distance. As you said, it’s always reporting a little bit more effort than I’m giving. Good luck on your race.