Hercules star Dwayne Johnson’s gruelling dietary regimen gave the actor a superhuman physical edge

IT’S hard to think of an actor more qualified to play the Roman demigod Hercules than semi-retired WWE wrestler Dwayne Johnson, aka The Rock.

HERCULES, son of Zeus, would surely have been a strapping male specimen.

So it’s hard to think of an actor more qualified to play the Roman demigod than semiretired WWE wrestler Dwayne Johnson, aka The Rock.

At 1.96m tall, and built like the proverbial brick sh — house, Johnson already cuts a larger-than-life figure in the cultural imagination in films as diverse as The Tooth Fairy and G.I. Joe: Retaliation.

But the 42-year-old force of nature, who recently finished shooting $100 million earthquake movie San Andreas on the Gold Coast, has revealed that he faced a decade-long struggle in getting his pet project off the ground.

Super-size me ... director Brett Ratner on set with Johnson.

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Johnson says he first mooted the idea of playing the mythical Roman demigod with studio bosses about the same time he landed his first lead role in The Scorpion King (2002).

“But I didn’t have the capability to green light anything back then. Because I came to Hollywood in a non-traditional way, my goal was to break in and transition into becoming a good actor, which I knew took a lot of time.”

Over the next five years, Johnson went on to carve out a solid career for himself in films such as Walking Tall, Game Pla n and Be Cool, in which he played a gay, country western-singing bodyguard.

But when the actor finally felt like he had mustered enough box-office clout to start seriously pitching his version of the Hercules story to the studios, he hit another roadblock.

“At the time, they were going after much smaller actors to play the action hero roles,’’ he says.

“That’s how Hollywood works. When Tobey Maguire becomes an action hero, then other actors who are smaller tend to get cast as these men of action, men of physicality.”

Johnson, who is widely considered to be one of the all-time professional wrestling greats, didn’t become a 10-time world champion by throwing in the towel.

And eventually, he persuaded studio bosses to beef things up a little bit.

Bare essentials ... Johnson really had no place to hide.

“The (Steve Moore) graphic novel deconstructs the myth of Hercules in a really interesting way. And we had to deconstruct the studio’s version of Hercules at the same time,’’ he recalls.

“We said: what if we give the people a version of Hercules that they would expect a half man, half God to be. With everyman issues but still a physicality.

“Hercules to me should be larger than life.

“That was my pitch to the studio: when I was a kid I wanted to live vicariously through this man whose physicality had reached a peak.”

When it comes to playing a man of mythological muscle, Johnson certain had a headstart. But even he had to subject himself to a gruelling physical regimen to give his character a superhuman edge — particularly since the costume barely covered 50 per cent of his body.

While filming in Budapest, the set his alarm clock for 3.30am each day so he could fit a cardio routine in before breakfast. He also squeezed a gym strengthening and conditioning session before he started filming.

“We were also fighting daylight. In Budapest at that time the sun was going down fairly early,” he explains.

Man of myth ... Johnson’s Hercules is big and mean.

Somewhere in the shooting schedule, Johnson also had to find time to wolf down six whole meals a day — fish, chicken, steak, carbs, greens.

It was the sort of monastic diet and exercise program of an elite athlete might follow — with one crucial difference.

“I have been fortunate enough to have been both an actor and an athlete, and the difference is a lot of athletes will prepare for one day, and peak for one day,’’ says Johnson.

“The challenge for me was holding the peak for four months.”

Every 72 hours, Johnson was required to strip down to his underwear for an all-over set of photographs which were then examined by his diet coach in minute detail.

He responded with a list of dietary tweaks that would “draw out a little bit more water or add a little bit of fat” in the interests of continuity.

“There was a lot of grainy muscle and a lot of vascularity,’’ explains Johnson.

“When your body is operating like that, and everything is stressed every day, the slightest change — maybe I get six hours sleep, compared to 8, maybe I had a little too much sodium — will really show on your body.”

It’s that sort of extraordinary commitment and discipline that made Johnson the highest-grossing actor at the box office last year.

The big picture ... Johnson in the Michael Bay film Pain and Gain.

Johnson’s combined tally, thanks to hits such as Fast and Furious 6, G.I. Joe: Retaliation and Pain And Gain, was a whopping $1.36 billion in 2013.

With a windfall like that, most of us mere mortals would at least consider an early retirement.

Not Johnson.

“It never crossed my mind,’’ he says.

“If anything, I thought now is the time to kick it into gear even more. Now we have clout, how can we leverage that in terms of relationships, movies that are in development that I want to bring right up to the pole position and get made.

“Having that type of success allows for that direct phone call to the chairman of the studio saying: let’s make this movie, let’s partner up.”

The next Dwayne Johnson film scheduled to hit cinemas is Fast and Furious 7.

Originally slated for release this month, the film delayed by the death of co-star Paul Walker will now open in Australia in April 2015.

Action replay ... Johnson and (Elsa Pataky) in Fast & Furious 5.

Johnson had already completed most of his scenes when Walker was killed last November in a car accident.

“Ninety-five per cent of my work was already done’’ he says.

“I only have a day or two of shooting left but I haven’t seen any footage yet.

“After (Paul’s) passing, I spoke to Ron Meyer, at Universal, and we agreed that the best thing we could do is create a little bit of space out of respect.

“We’ve all had that experience when we lose someone, it jolts us, we hug each other a little tighter, let the small stuff fall away.

“I loved Paul. He was a beautiful guy and an amazing dad and I enjoyed the talks we had about the bond between a daddy and his little girl.

“I miss him dearly. For me, it’s all about his family, sending them strength.”

Hercules opens on Thursday.