Jersey Shore’s Pauly D Debuts Beefed-Up Look

Pauly D on December 31, 2011 and April 22, 2012. Ethan Miller/Getty Images; DJDM/

Looks like Pauly D may have upset the delicate GTL balance.

During an appearance at the Hard Rock Hotel in Las Vegas this past weekend, the Jersey Shore star (real name: Paul DelVecchio) stepped out looking noticeably bigger.

A source close to the DJ tells Us Weekly DelVecchio, 31, has put on some weight recently–but only because he's been logging extra hours at the gym.

"He's gained 20 pounds of muscle," the insider shares. "He is [exercising] nonstop . . .three times a day sometimes."

Between his ramped-up workouts and his DJ gigs, DelVecchio has plenty to keep him busy these days. The Rhode Island native is also currently appearing in a Jersey Shore spinoff–The Pauly D Project–with his close friends Ryan Labbe, Gerard "Big Gerry" Gialanella, Jason "J-Rock" Craig and Michael "DJ Biggie" Morgan.

"The whole world, they know me from Jersey Shore. They know I can party in Jersey with some strangers that become my friends, but now with my show, you get to see where I came from, you get to meet my family, my friends, and see what it's like on a daily basis being a touring DJ," DelVecchio told Us last month about how his new series compares to the show that launched him to stardom.

Added his pal Craig, "It's kind of like the pros. . . Seaside's like Little League."

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