Zac Efron gives women a reason to buy Men's Health magazine

zac-efron-mens-health.jpgApparently Men's Health is a magazine for men who want to be healthy... but we're guessing the demographic of their average reader may shift this month as a result of Zac Efron's rippling biceps.

There are two covers -- on the subscribers' version, below, Efron shows off one of his two tattoos, a feather cluster on his inner bicep. ( His other one is on his hand. It says "YOLO.") He bulked up significantly last year while he was shooting the movie.

"Physically I started eating a lot," he says. "Eating through walls. Just eating and eating. That's all I'd do and I put on some weight that way. As far as the training goes, just trying different techniques and methods."

When he went to meet real marine sergeants in order to prep for the role, he realize he had some work to do. "I was blown away. I was taller than most of the guys, but they were just thick, like there was something about them. They had a definite presence," he says. "Here I am, slouched over and I just smile a lot. I'm just always smiling. These guys were always serious. Honestly, it was one of the most awkward moments in my entire life."

Bulking up helped him get into character. "It's one of the only concrete things that you can do to feel differently about a character. [Before,] I didn't feel like a Marine. I didn't have the posture. I didn't feel like I had the presence and that was just one thing for me that I could do to really up that change."

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Photo/Video credit: Men's Health