Saturday, September 02, 2006
The Danville, Illinois, website, All Around Danville, has a lot of stuff in it. If I ever actually visit Danville (as opposed to this virtual visit), I'll be sure to check it out. For today, I just grabbed a couple of images from their history page. Above, the Fischer Theater. Below, Harmon Mansion.
I borrowed a couple of issues of Runner's World from the library a week or so ago, and one of them gave me a pointer to this site at USA Track and Field. It is a site that uses global mapping technology to help you map and measure a route. It's pretty precise. It can tell me all the streets in my home town (although I've found a few inaccuracies.) I can see how that would be useful, and a lot easier than going out and driving your route to measure it with your odometer. But of course I didn't need it, because I've got the Forerunner. Right?
Well, after yesterday, I don't trust the Forerunner. So I decided to put it to the test. I used the USATF site to map out a four mile route, and then ran it with the Forerunner. Sure enough, the Forerunner measured it at 4.72 miles, almost a 20% error. I even have a pretty good idea of when it happened, too. The first three miles went by just about as expected, and then somewhere in the fourth, I got the "Weak GPS Signal" beep, and the fourth mile ended much sooner than expected. I also used the USATF site to go back and approximate the mileage on my half marathon from Monday, and I'm pretty sure it was short, too. It was more like 11 or 11.5.
So, I don't know what I'm going to do. I guess I'll get rid of the Forerunner. It's no good to me if I can't trust it. I'm not going to go back and adjust my previous mileage. I'm going to trust that during the time I was estimating my mileage by my time, I underestimated by enough miles to make up for whatever overage the Forerunner has given me. So by golly, I really am in Danville today!
Posted by USJogger at 8:18 AM