WATCH: What's the Secret to Zac Efron's Chiseled Physique? His 'Neighbors 2' Costars Spill His Secrets

How does Zac Efron stay in such good shape? His Neighbors 2 cast members spill his on-set secrets

Photo: Everett Collection

It’s no secret that Zac Efron is in great physical shape. See: the shirtless scenes from his recent films, along with this handy gallery of shirtless photos.

Efron’s toned torso is once again on full display in his latest film Neighbors 2, so when PEOPLE sat down with Efron and his costars recently, we had to ask about the secret to his success.

“When you’re around Zac’s body and it’s exposed, you just want to touch it,” admits director Nick Stoller. “And they all were excited just to get to touch it.”

“He doesn’t eat much fun food,” adds Chloë Grace Moretz. “He has a lot of protein shakes and he works out like 12 times a day. He always [works out] with a stretchy band, always.”

Efron himself admits that it’s a lifestyle choice that isn’t the most fun, but pays off in the healthy-living sense.

“It’s part of what you do, it’s part of the process,” he says.

“He’s usually doing push-ups in the corner of the set,” adds Stoller. “He setup a weight area that I discovered on the set.”

“I once saw Zac walk up a tree between takes,” reveals Seth Rogen. “I looked over and he was 30 feet up a tree.”

Moretz appreciates Efron’s commitment, but admits that particular discipline is not for her.

“It’s a lot of dedication,” she says. “I’m happy to not have abs.”

Stoller says those muscles deserve some appreciation.

“I was really tired one day and he was standing there shirtless because we were filming some shirtless scenes. I said, ‘Can I feel your bicep?’ ” he recalls with a laugh. “And he said, ‘Okay!’ And it was amazing.”

Neighbors 2 hits theaters May 20.