About Utah Undie Run

2,270. That's how many 2011 Utah Undie Run attendees broke the Guinness World Record for the largest gathering of people wearing only underwear. These days, the annual 5k opens with a count to see if it can beat its 2011 milestone. Then, runners—whose shed clothing is donated to the homeless—sprint toward the finish line donning bras, boxers, and swimwear. In lieu of athletic clothes, they cover themselves in body paint that express things they'd like to see change in Utah, such as adding pepper to the state's notoriously salty lake.

Those messages might earn participants top prize in the body painting category of Utah Undie Run's costume contests, whose other categories include biggest undies and best wild card. The contests take place at the race's after party, a freewheeling festival of bounce houses, mechanical bull riding, and live DJs.