This evening, I ran a five-mile road race in South Boston that I signed up for at the last minute. Normally when I run races, I go solo, with the exception of the Chase Corporate Challenge, when my good friend Karlyn caught up with me for the last 3/4 of a mile and we pushed each other to finish strong.
I ran tonight's race with another friend. We ran together, of course with him saying that I'd probably be faster than him, and me realistically knowing that he would be pushing me hard to run faster than I normally would, and that I might have to drop behind him. As it turned out, he was a good pace, and we finished the race together. My official time was 47:29, though we started 30 seconds later, and so I really ran it in 46:59. That's about 9:20 per mile.
That's why I like running/biking/swimming with other people -- they push me to be a better athlete.