J.K. Simmons stunned the Internet when his trainer posted photos of the actor's massive biceps, which he says is part of his healthy lifestyle

Credit: Source: Aaron Williamson/Instagram

J.K. Simmons is dedicated to his new, healthy lifestyle!

The 61-year-old actor stunned the Internet at the beginning of June when his trainer shared photos of Simmons’ incredible muscles, with fans speculating that he was bulking up for his role in the new Justice League movie.

But not so, says Simmons. His insane biceps are just a side effect of his love of the gym.

“This is all coincidental,” he told Business Insider. “I’m not going to mess with something that iconic,” he says of his character in the Justice League, Jim Gordon.

It’s all just a continuation of a healthy kick Simmons has been on since 2009.

“After the second and final time that I got hugely fat in my life and when I lost that weight six or seven years ago, I pretty much decided that I was going to stay in decent shape for the rest of my life,” he explains.

The first time was in 1997, when he was playing a neo-nazi inmate on HBO’s Oz.

“I was not in good shape at all,” Simmons says. “I was overweight and soft and here I am playing the head of the Aryan Brotherhood in this maximum-security prison in the first-ever HBO original drama and I was watching the first season when it came out and I just thought, ‘Wow, I don’t believe this guy at all. I have to get my a– to the gym and be a believable hard-a–.’ ”

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And then in 2009, Simmons hit 250, and decided to kick his bad habits for good. He worked with trainer Dana Perry to get in shape, working on overall fitness and building muscle.

“I’ve gone back and forth with fine-tuning the kind of conditioning I’m doing,” he says. “Sometimes trying to shed weight and getting leaner and sometimes trying to pack on a little more muscle.”

His recent muscles, though, came from working with Perry and Aaron Williamson, the on-set trainer for Terminator Genisys.

“I just had free time to go to the gym, so I started training with him,” Simmons says.

Williamson, who also trains Zac Efron and Dwayne Johnson, posted the viral photos, adding, “Every time we train together I forget he’s 61 years old. So much respect for this guy #OldManCranking”

Watch out for Simmons now though, he jokes.

“Those were shot at the end of April. I’m huge now!”