Credit: Splash news online

The Jonas Brothers are all grown up!

Nick, 18, and big bro Joe, 21, showed off their bulging biceps while playing football on the beach in Hawaii Wednesday. Flaunting their impressive six-pack abs, the Camp Rock 2 stars -- sans older brother Kevin, 23 -- cooled down with a midday swim.

Earlier this month, Joe told Details that he and his family had never been to the Aloha State. "We've seen every state in America besides Alaska and Hawaii, been all over Europe," he said of the group's rigorous touring schedule. "It's been so much fun."