Warning! These Pictures of J.K. Simmons Flexing His Muscles at the Gym Might Give You Whiplash

J.K. Simmons has been hitting the gym.

The 61-year-old actor has seriously bulked up over the past few months, training with fitness pro and former Marine Aaron Williamson.

Williamson shared some shots of the now-bearded actor's workouts on Instagram recently, and Simmons looks well and truly pumped. While he's always had a slim frame, it's clear he's gained serious muscle his cut arms and shoulders.

"Every time we train together I forget he's 61 years old."Williamson wrote. "So much respect for this guy."



Another trainer John Meadows gave Simmons the nickname "#OldManCranking."

"He's making me look bad," Williamson wrote in another post, adding Simmons wasn't playing games when it came to his fitness.

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The Farmers Insurance spokesperson appears to have been training with Williamson for at least six weeks. "Saturday morning, 61 years old and making the young generation jealous," the trainer captioned on post. "This is what dedication looks like."

Simmons, who won an Oscar for his role in 2014's Whiplash, is currently filming Zack Snyder's superhero flick Justice League. He plays Gotham City's Commissioner Gordon, alongside Ben Affleck's Batman, Henry Cavill's Superman and Gal Gadot's Wonder Woman.

No word on whether Gordon will be fighting with the DC superhero all-stars, but with his new guns, it looks like he'd be able to hold his own.