Watch: Hugh Jackman talks about bulking up to play Wolverine in Deadpool 3
And he's going all out with his eating and exercise routine to get in shape.
Appearing on This Morning, Jackman said his food is all measured out for him, to make sure he takes in exactly the right amount.
He takes in around 5500 calories, 3000 more than the NHS says the average man requires.
"I don't question anything," he said of the meals he's given by the trainer he is working with.
"Food arrives and it's been counted out and it's 600 grams of carbohydrates and it's 270 grams of protein... and a certain amount of fat, I can't remember the grams, and then I have to eat that food for the day."
Read more: Everything we know about Deadpool 3
The star admitted his wife Deborra-Lee Furness isn't all that sympathetic when he complains about having to eat so much.
"I can't tell you how many times I'm like, 'Oh babe, I've got to eat again' and my wife is like 'Shut up!'" he laughed.
"Having me complain about eating? She's like, 'Oh poor you, oh you have to have another bite!'"
The actor said when he first started playing Wolverine more than 20 years he had no idea what it took to get in that kind of ripped shape.
"I knew nothing when I went into these films," he said.
"I just thought, pump up is two weeks.
"In fact, in X-Men one, if you look at it, I was cast three weeks before filming and all the scenes with my shirt off had to be pushed to the end... there is one shot, it was the first thing I shot, and the director was trying to hide my body!"
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