Arnold Schwarzenegger's Body Evolution

USMagazine, Monday, July 30, 2012, 4:00pm (PDT)

From Mr. Universe to Governator, nobody has had a career quite as varied as Arnold Schwarzenegger's.

The Austrian-born action star -- who celebrated his 65th birthday Monday -- first made a name for himself as a competitive body-builder in the mid-1960s. The 6'2 Schwarzenegger began weight training at the age of 15, and would go on to win Mr. Universe at just 20 years old.

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Schwarzenegger made the leap from weight-lifting to the big screen in the early '70s, appearing in The Long Goodbye and Stay Hungry, which landed him a Golden Globe. He became a household name with his star turn in 1982's Conan the Barbarian, playing the titular prehistoric hero out to avenge his parents' deaths.

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A registered Republican, Schwarzenegger -- who wed Maria Shriver, a Kennedy, in 1986 -- traded in his itty-bitty swim trunks for good in 2003 when he announced his candidacy for Governor of California. The Terminator star was ultimately elected, and would go on to serve out a full term as the state's governor after his re-election in 2006.

Now that his gubernatorial stint is up, the Total Recall actor plans to head back to Hollywood; he is set to appear in The Expendables 2 later this year.

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"They said to me, 'Well, we know you've been out of the business for eight years. Let me show you how to load a gun again . . . Here's how you throw a punch and here's how you kick,'" Schwarzenegger told the crowd during a Comic-Con panel discussion about filming the action flick alongside Sylvester Stallone. "But they soon realized I didn't lose it at all!"

Click through to see how Ahh-nold's pumped-up physique has evolved over the years.

This article originally appeared on Usmagazine.com: Arnold Schwarzenegger's Body Evolution