See which Jay Z song fuelled John Krasinski's Navy SEAL workouts

The Office's Jim Halpert would definitely crack a joke to hide his utter amazement! After just four months of gruelling training, John Krasinski has debuted a completely transformed physique on the cover or Men's Health. The actor plays a Navy SEAL in 13: The Secret Soldiers of Benghazi, and admits it was no easy feat getting this buff.

“I gotta be honest: It was brutal at times,” the 36-year-old revealed in the interview. “We did tons of metabolic work, dragging sleds and all this stuff I’ve seen NFL players do.”

Despite it being a challenge to transform his body, John said that “getting stronger every day is thrilling.” Emily Blunt's husband had just four months to get in SEAL-ready shape, so to prepare for the taxing role he enlisted the help of celebrity trainer Jason Walsh.

And the training certainly paid off. John smoulders on the cover of the men's magazine, showing off his bulging muscles in a black tee.

As far as his favorite workout goes, the father of one said he enjoys bench pressing. He explained, “There’s that number you can keep pushing. It’s almost a game instead of a workout.”

But it couldn't all be fun and games. John admitted there is one workout that he is not keen on doing: the “Bulgarian split squat,” which involves doing a 1-legged squat with a rear foot elevated. No easy feat!

Thankfully for John, working out is easier when you have a fun playlist. The former star of The Office admitted his go-to track is “What More Can I Say” by Jay Z. Well, looking at the results of the actor's workout has probably left more than one fan speechless!

13 Hours: The Secret Soldiers of Benghazi hits theatres Jan. 15, 2016.

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