'Justice League': JK Simmons Says His Muscles Are All Natural

Stephen Colbert is as impressed with JK Simmons' physique as Justice League fans.

Simmons was a guest on The Late Show this week. Colbert showed off a photo of Simmons in the gym. The photo had stunned the internet when it was first revealed and Colbert was equally impressed.

"My friend's kid called that shredded Santa," Simmons said.

Simmons also wanted to get it on record that at 63-years-old his physique is all natural.

"There was no juice involved," he said. "It was all natural. Let me just put that out there. Not eating the spinach. Just going to the gym."

You can watch the interview in the video above.

Simmons plays Commissioner James Gordon in Justice League and the DC Extended Universe. In a previous interview, Simmons admitted that the role intimidated him at first.

"There was definitely a little bit of an intimidation factor but I wasn't going to sit down in my living room, get out my DVDs and watch Gary Oldman," Simmons said. "I obviously had a tiny little part in the first movie and I did more reading of comics and talking to friends who were comic book aficionados rather than watching or listening to the wonderful actors who have played that character in the past."

Simmons first became known to comic book movie fans by playing J. Jonah Jameson in the original Spider-Man Trilogy. Simmons says he'd be up for revisiting the role if the opportunity arose.

"That was a great, great time and huge for my career and my life, and just pure fun. If there were an opportunity to revisit that," he said. "I don't know though. How old is Spider-Man going to be if J. Jonah Jameson is this old?"

Justice League currently has a 60.72 ComicBook.com Composite Score and a 3.68 out of 5 ComicBook.com User Rating. Let us know what you thought of Justice League by giving the movie your own ComicBook.com User Rating below.

The film will be followed in the DC Extended Universe by Aquaman on December 21st, Wonder Woman 2 on November 1, 2019, Shazam on April 5, 2019, Cyborg in 2020, and Green Lantern Corps in 2020.