Dwayne Johnson is pleased not to "look pregnant" after slimming down to play a 75-year-old man in a new movie.

The 53-year-old star put on 30lbs for film The Smashing Machine, but he is now channeling his inner 75-year-old Clint Eastwood for a role as Chicken Man in Benny Safdie's forthcoming film Lizard Music, and he is "happy" to not be carrying as much weight.

He told Variety: "I've been dieting. Happy to not be carrying all the weight.

"I feel good I'm able to tuck in my shirt now.

"I am slimming down for our movie. Lizard Music - can't wait.

"I don't look pregnant, so it's all good.

"I'll stay in this zone. This is for my next movie with Benny, Lizard Music, where I play a 75-year-old man.

"Think Clint Eastwood at 75.

"Sinewy muscles, he's lean. But it feels good."

Johnson feels "much better" since dropping several pounds for a big screen adaptation of Daniel Pinkwater's novel of the same name, which tells the story of a young boy who befriends the Chicken Man to find an invisible island full of intelligent lizard musicians.

He added: "I gained 30lbs for the role in The Smashing Machine, so it's good to get it off.

"And I had to maintain it for live action Moana, so it's seven months, man, 30lbs is a lot. That's a lot. It weighs on you.

"But I feel good. I feel much better."

Last month, the WWE star told how he was eating less chicken in a bid to slim down.

Speaking during a career retrospective at Toronto Film Festival, he said: "This is me slimmed down. In the process of slimming down. I still have a long way to go.

"I'm so excited to get a chance to hopefully transform again like I was able to do in Smashing Machine.

"[It means] eating less chicken.

"Benny pitched me this after [Smashing Machine].

"And after about 45 minutes, this pitch ended and I said, 'I am your Chicken Man.' "