Dwayne 'The Rock' Johnson's insane 8,000 calorie diet he had to keep up to maintain his former physique

Dwayne 'The Rock' Johnson has been strutting his stuff with a leaner physique after he lost a decent amount of weight to appear in The Smashing Machine.

The movie has him playing MMA fighter Mark Kerr and while they're both big fellas, it's reckoned that The Rock shed about 60lbs for the role.

He's still a big guy, as you'd expect from him playing an MMA fighter, but not quite the size we've come to expect from Dwayne Johnson.

A wig and some prosthetics have helped him look pretty different for The Smashing Machine, which has been getting some good critical buzz ahead of a cinema release next month, while people have been appreciating his new look.

The Dwayne Johnson we've come to know is a veritable giant of a man and to reach that size takes a lot of exercise and one hell of a diet.

Even having lost a lot of weight Dwayne Johnson is still huge (Gisela Schober/Getty Images)

Back in his wrestling heyday, he said he would consume up to 8,000 calories a day, four times the recommended intake for a grown adult, and he remembered that he was 'eating many pounds of food per day, including a lot of cod'.

For breakfast, The Rock told Delish he tended to have cream of rice or oatmeal along with buffalo and eggs when he woke up, he'd also add fruits like papaya and blueberries into the mix.

Once he'd crushed the first workout of the day, he'd have a meal of something starchy such as rice or sweet potato, along with a dollop of protein in the form of chicken or steak.

His third meal of the day would be rice and assorted greens with chicken or buffalo, and throughout the rest of the day he'd be eating fish - which was usually cod or salmon - and then before bed he'd have a balance of carbs, protein and greens to give him the right sort of diet to transform into muscle.

That is a lot of food, and for a man who eats big on his diet he also eats big on his cheat days, which he absolutely loves as he can head somewhere that does a damn good cheeseburger and follow it up with 'some sort of sugar blast'.

He reckons he was eating as much as 8,000 calories a day at his largest size (Matt Winkelmeyer/WireImage)

However, that's only viable one day a week as the other six were for workouts and salmon, lots of salmon.

The Rock also experimented with his own energy drinks by mixing powdered caffeine to powdered amino acids and powdered carbs.

On his Instagram, he's shown that he also consumes peanut butter and supplements his diet with coconut oil and fish oil to provide some fat.

The quantities at which he's eating certain foods are impressive, as his meat or fish in each of his meals is said to be at least eight ounces.

In a typical day, Healthline reports he might be eating two eight ounce steaks, another eight ounces of chicken, almost 30 ounces of fish, 24 ounces of potato and finishing the day with a 10 egg omelette.

This goes into fuel for his gym sessions and helps maintain the mass of muscle he carries around with him, even if he's slimmed down for The Smashing Machine he'll still be eating very sizeable portions of food.

One sympathises with his toilet.

The Smashing Machine releases in cinemas on 3 October.