I don't think I've ever done this. When I enter a race- even a free one- I go all out. I did run a half marathon once as a tuneup for my marathon because the terrain was going to be very similar but I also PR'ed that half. And, it gave me a lot of confidence going into the marathon that I could handle the terrain. I've also run the race in my town, put on once a year, mainly just because it's here. I do go all out but I know that I'm only going to be as good as my buildup for the race was.
I rarely race. I run lots of races, though:
-they inspire me to stay trained
-I stay faithful to my running practice throughout the entire year by having to always be ready to complete a certain distance
-It's my favorite charity. I get to do one of my favorite activities by running for the variety of good causes.
-I get to know communities better by running in their races.
-the social benefits can't be beat.
Once in a while I even run faster than usual and place in age group!
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