EXCLUSIVE: Kevin Hart & The Rock Compare Workouts on 'Central Intelligence' Set

Everybody knows Dwayne "The Rock" Johnson is a beast in the gym, but Kevin Hart might be giving him a run for his money!

The Central Intelligence co-stars have a habit of posting their workouts on their Instagram pages and each agreed that they're the most dedicated fitness fanatics the other knows.

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"I beat the sun up at four o'clock in the morning," Johnson told ET about his early-morning workouts, pointing at Hart. "There's one man on this earth that does that, too."

ET's Kevin Frazier caught up with the stars on the set of their upcoming film.

"Our days on set are filled with nothing but love and appreciation," Hart said.

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Johnson and Hart play high school buddies who reunite in the action-comedy. As his 20-year high school reunion approaches, a once-popular jock (Hart) is contacted by a former classmate who was bullied and humiliated back in the day (Johnson). Now the "geek" is a contract killer for the CIA, who ropes him into a secret and deadly operation.

Central Intelligence hits theaters June 17, 2016.