Hollywood actor Austin Butler has unveiled the total transformation of his physique on the cover of the latest issue of US Men’s Health magazine.

Butler, 34, is preparing to play an alcoholic ex-baseball player Hank Thompson in his new movie, Caught Stealing.

The athlete turned bartender becomes entangled in crime in New York, in the 1990s.

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Butler, who is around 182cm, went from 68kg to 83kg.

Butler said the director of the film, Darren Aronofsky, asked that he focus on creating a thicker booty for the role.

“I actually have a whole section of just baseball players’ a**es that he would send me,” Butler told the publication.

“He was like: ‘Look how thick they are!’”

Butler said he chugged pizza and beer in order to gain weight for the role.

However, he did say the alcohol intake was difficult: “Drinking has never been my thing. I don’t like the way it makes me feel.”

Butler worked with personal trainer Beth Lewis, who also worked with Hugh Jackman for Wolverine.

Butler explained he loved training with Lewis, balancing on a BOSU ball and doing one-arm kettlebell moves. He also admitted to doing a “tonne of hip thrusters,” to help grow his behind.

“I’ve got a whole section of Celine pants that I just can’t even wear anymore,” Butler said.

The actor explained his initial thin physique was a result of being in the midst of awards season, where he sometimes forgets to eat.

Butler is known for changing his physique, including for his role in Elvis, which was partially filmed on the Gold Coast and saw him loading up on ice cream and doughnuts.

For Dune: Part Two, he worked with an ex-Navy Seal turned trainer, Duffy Gaver, where he stuck to a diet that included lots of brown rice, chicken and broccoli.

The new film Caught Stealing is set for US release on August 29.

The cast includes Zoe Kravitz, Regina King, Bad Bunny, Matt Smith and Liev Schreiber.