Flashback: Gerard Butler's '300' Training Regimen

In 2007, an action film based on the 300 comic book series hit theaters with a bellowing roar. To play his ferocious character of Greek hero King Leonidas in the film, Gerard Butler had to do some intense training, which he describes in our featured flashback.

While it's unknown just how burly the real-life Leonidas was in 480 BC when he challenged an entire Persian army with just 300 Spartans, legend has it that he was a strong man in many capacities.

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Therefore, Butler was subjected to a pretty intensive training regime to look the part for the film. As Butler recalls in the flashback, it was a grind—and a journey—to train for his character.

"[It was] not eight weeks for me; it was seven months," Butler recalls. "...I think after eight weeks...I could have got in pretty good shape, but after seven months, that's how you get like I did eventually.

"...You just keep stepping over little barriers. ... I would honestly think, 'I can't get [any more muscular]. This is great,' and then the next minute, you'd be like, 'Oh, wow, I've surpassed that!" and then you're enjoy it 'cause you know, 'I'll never be like this again!' so you think, 'How much more can I push it?' That was the Spartan element."

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Butler revealed that although he had to work tirelessly to power through rigorous circuit workouts and lifting weights on set, the Scottish actor didn't have to work nearly as hard to channel his character's rage.

"I think it has a lot [to do with] the Scotsman in me. It's not difficult to get that fire out of a Scotsman," the then-37-year-old actor says. "I think it's in our blood. We spent too many years fighting like the Spartans. ... That was an easy part; the problem is honing that and making it skillful."

Although Butler's brawny figure and fervor were genuine, the film's location was entirely fictionalized, as it was shot on a digital backlot draped in blue screens. The technology has previously been used in other films, but it was relatively novel and viewed as cutting-edge.

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"It was all [filmed] in the same studio, so there was a real controlled element," he says of the film's production, which began in October 2005. "...We did this film really quickly, like sixty days we shot it."

Despite the potential for his character, who dies in 300, to live on in the upcoming prequel 300: Rise of an Empire, Butler will not appear in the film.

300: Rise of an Empire is in theaters August 2.