Hammer time: Chris Hemsworth muscles up for 'Thor'

Hammer time: Chris Hemsworth muscles up for 'Thor'

When Kenneth Branagh signed on to bring the action epic "Thor" to the big screen, the Oscar-nominated director scoured Hollywood for an actor who could embody Marvel Comics' hammer-wielding superhero.

Aussie newcomer Chris Hemsworth was the answer to Branagh's prayers.

Hemsworth, 27, first turned heads in J.J. Abram's 2009 blockbuster, "Star Trek," where the actor delivered a brief but memorable turn as Captain Kirk's strapping young father, George Kirk.

But the 6-foot-4-inch actor had to pack on the muscle to shoulder the burden of selling Branagh's $150-million take on the Marvel franchise.

"Chris gained about 20 pounds. But you can't get a physique like this with kettle balls and gadgets. You've got to go old school," said Duffy Gaver, Hemsworth's personal trainer on "Thor."

The Santa Monica-based fitness guru whipped Brad Pitt into shape for the 2004 war epic, "Troy."

The former Navy Seal and Marine Corps sniper also helped Tobey Maguire get fit for 2002's "Spider-Man."

"In every film project, you have to decide how your star character has to look," Gaver told CTV.ca.

For example, Maguire need to look like a fit teen in "Spider-Man."

"Too much muscle would have just looked weird," said Gaver.

Pitt also had to avoid bulking up too much for "Troy." Otherwise his performance would have suffered in the film's ancient setting.

Thor, however, is supposed to be superhuman.

"We needed to create a very different body to pull this movie off," said Gaver.

Hemsworth buffed up, did his own stunts

That meant intense, daily, 1 ½-hour workouts filled with squats to strengthen Hemsworth's legs and repetitions with heavy weights to bulk up the actor's arms.

Hemsworth also embarked on a protein-intensive diet spiced up with veggies, some fruit and controlled portions of good quality cards.

"If you want a body like Chris has now you've got to work for it," said Gaver.

"You need eight hours of sleep each day. You have to workout faithfully and eat a clean diet with lots of lean protein. These rules don't just apply for Chris. They apply to everyone," he said.

The duo's efforts clearly shine in "Thor's" trailer, where Hemsworth fills the screen with arms that seem forged in an ancient Nordic furnace.

But Hemsworth's own competitiveness played a big role in his transformation and his performance.

"Chris is a very competitive guy. That's the way we trained with one another," said Gaffer.

That competitive streak, coupled with Hemsworth's natural physical abilities, were a blessing to Branagh's production.

Hemsworth did 99 percent of his own stunts.

"Chris was capable of 100 per cent, but we didn't want him to get hurt," said "Thor" stunt coordinator Andy Armstrong.

The final product is filled with big, eye-filling action sequences that hold their own against a classic like "Ben-Hur."

"The great thing about Chris is that he did far more stunt work in ‘Thor' than Charlton Heston did in ‘Ben-Hur," said Armstrong.

"Personally, I like Chris' fight sequences best of all in ‘Thor' -- and that's all Chris. What he does here feels so organic and so real. This guy could make a living as a stuntman any day of the week."