Gym is John Caldwelllife for the Ken dolls.

In Greta Gerwig's upcoming Barbie, Ryan Gosling and Simu Liu's characters have an epic "I'll beach you off" kerfuffle. But it turns out, the Kens are also competitive about pumping iron. 

"Greta was very deliberate in what she wanted the Kens to do to bond," Simu exclusively told E! News' Francesca Amiker, "which was to gym together."

"So, while the Barbies were having a nice, relaxing night," the actor continued, referencing the fun-filled sleepover the female cast members like Margot Robbie and America Ferrera got to enjoy, "the Kens were lifting things and flexing."

And no one took the task quite as seriously as Ryan. 

"I could not beat this man to the gym," Simu admitted. "No matter how early I went, he was always there. He always stayed later than me. So, I really saw the discipline and I really saw the Ken-ergy."

However, as Simu noted, the Kens didn't have too much FOMO over the Barbie sleepover. For one, they were able to virtually join in on some of their shenanigans. 

"We were invited to Skype in," he teased. "It was definitely a bonding time for the Barbies."

But there is one cast gathering the Shang-Chi actor still regrets missing.

"I had to fly back to Toronto to host the Juno Awards, which was amazing, but everyone else rented a massive limo and watched Magic Mike Live in Piccadilly Square," Simu admitted. "They all Facetimed me from the limo as if I wasn't going to die of jealousy."

While the 34-year-old had to skip out on an epic Barbie cast outing, he explained that they spent a lot of time together outside of filming. As he put it, "We had a lot of dinners, a lot of hangs."

And although they have since wrapped, Simu explained that he's still got unfinished business with one of the Kens.

"Scott [Evans] and I had a very, very, very long and very contentious table tennis rivalry that lasted over the course of the entire production of the movie," the Marvel actor said. "I can't remember who won, he probably beat me last."

He added, "I hope I get to see him again soon because I need to get him back."

We can only hope the cameras are rolling for this face-off.

Barbie hits theaters July 21.

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