JoJo rocks a pair of ripped jeans at the 2012 Nautica South Beach Triathlon on Sunday afternoon (April 1) held in Miami Beach, Fla.

The race, which benefits St. Jude Children’s Hospital, expected more than 3,000 athletes including Josie Loren, James Marsden and Jake T. Austin.

PHOTOS: Check out the latest pics of JoJo

“Just did a test run for this @nautica South Beach Triathlon tomorrow. Training is about to get serious,” Jake tweeted the day before the race.

In 2011, the event raised over $275,000.