Some 4,000 triathletes are planning to swim, bike, and run their way through the city this Sunday, starting in the Hudson River and ending up near the Bandshell in Central Park. But yesterday evening, in a ridiculous warmup event of sorts, about 100 people took off most of their clothes, added a tiny bit of costume, and ran their cute little butts off in what has become an annual tradition, the totally silly, totally sexy Underwear Run.

The course covered 1.7 miles of the park, beginning and ending near Cherry Hill, and the winner (yes, these people can't help but compete, even when dressed like, say, a bunch of Minions) finished in an impressive 9:49. But the real draw of the Underwear Run is, of course, just seeing lots of people hanging out in their underwear, and all of the athletes arrived a good 30 minutes early to the Cherry Hill Fountain to goof around and take photos with each other and with the Grand Marshal, the Naked Cowboy.

There was a "Best Undressed" contest as well, which was won by the woman wearing the literal codpiece. But really? Everyone's a winner in the Underwear Run!

The 15th annual Panasonic NYC Triathlon begins on Sunday at 5:50 a.m., in the water at 96th Street and the Hudson River.