Leading up to the NYC triathlon, they have a few fun events to get people psyched up. There is a diaper derby at the expo and a doggy dash the morning of the race. On the Friday before the race they do their annual underwear run. It is 1.7 mile fun run with a few hundred people running through Central Park in their underwear. Considering the fact that most people are super fit triathletes, it is a fun event for spectators, too.