Been a bit serious lately, so here's a slightly less intense anecdote. In track races your legs are constantly in motion, and for the most part you don't really get out of the saddle. In longer races this can create an issue for one's genitalia. To be precise, sometimes your wang gets a little numb. This is no big deal whatsoever - track races are never long enough to do any permanent damage. When you finally get off the bike, however, all the blood rushes back into those precious areas and you end up with half a bar.
If it was a bigger race, and you placed, this tends to coincide with the time you need to go stand on the podium.