Chris Pratt gets buff for ‘Guardians of Galaxy’: See his before and after

"Parks and Recreation" star Chris Pratt frequently makes changes to his weight for his movie roles — more for "Moneyball," less for "Zero Dark Thirty," more for "Delivery Man." Now the actor is buff once again for his upcoming role as an interplanetary police officer in "Guardians of Galaxy."

Pratt, 34, posted a photo yesterday to Instagram of himself, shirtless in a gym, his rock-hard abs on full display. "Six months no beer," he wrote, with the caveat, "Kinda douchey to post this but my brother made me."

You may remember Pratt sharing a slightly less serious abs shot during a December 2012 appearance on "Conan." That time, the actor had muscled up to star in "Zero Dark Thirty," and his photo featured him in tighty whities.

By the time he appeared on "Conan," though, Pratt was a lot less chiseled, having gained back a lot of weight by drinking "supergross but pretty tasty" weight gain shakes. He had once again changed his physique in order to play a lawyer in the comedy "Delivery Man."

"This is what 275 looks like,” he told Vulture on the set of "Parks and Recreation" in September 2012. “All man right here.”

Pratt admitted that he wanted to gain another 25 pounds by November. “I just like to gain weight and lose weight," he said. "It’s a roller coaster. I just want to do this. I want to touch God."

So what is his actual resting weight?

"I've always been a little soft," Pratt told Conan O'Brien. "I like to eat."

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