DWAYNE 'THE ROCK' JOHNSON's diet and fitness regime is planned so that he's scene-ready "at any moment".

The wrestler-turned-actor is one of the best-paid stars in Hollywood, and his personal strength and fitness coach, Dave Rienzi, has revealed the secrets to his enviable on-screen appearance.

He shared: "We hold his conditioning in a very tight window to allow him to be ‘scene ready’ at any moment. Keeping him at striking distance ensures that we never need to take drastic measures to obtain a certain look, or over-stress his body.

"The bottom line is that he always needs to be able to perform at his best on screen."

Dwayne, 48, follows a strict regime that helps him to stay in shape and to look his best on screen.

Dave told Muscle & Fitness magazine: "The execution of his diet and training needs to be as nuanced and complimentary as possible to allow him to do that consistently."

Dwayne and Dave have recently been working together to help the actor to sculpt his physique for the much-anticipated 'Black Adam' movie.

The fitness expert hailed the film star for his "driven, disciplined, and determined" approach towards his workout regime.

Speaking about their efforts, Dave shared: "I definitely look at this with an artist’s eye for symmetry, detail, and proportion. It’s a fun process when you have someone like DJ who is so driven, disciplined, and determined to do the work.

"There’s a continuously evolving vision that we are always working towards. We’ve been building up to the Black Adam movie for a while, with this goal of creating a real-life superhero physique … with no padded superhero suit necessary."