The 65-year-old actor has been a movie star and the Governor of California, but claims he would not have been able to do any of it if he hadn't started exercising while he was growing up in Austria.
The seven-time Mr Olympia bodybuilding champion told Empire magazine: "When I started lifting I got compliments right away - 'Wow! You've been lifting for a month? This is incredible. Look at your muscles popping out!'
"It was the perfect storm. Bodybuilding got me into the movies, then movies got me into political office - because politics is all about name recognition. So it all goes back to bodybuilding. Without that I wouldn't have achieved any of the things that happened after."
The Terminator star also revealed that he always knew he wanted to leave Austria for Hollywood so had to work hard on his body to achieve his dream.
He said: "I'd felt from the time I was 10 years old that I was destined for something bigger than staying in Austria, even though at the time I didn't quite know what I was going to be.
"I remember buying this magazine and reading about a young kid in a factory town who trained hard, became Mr Universe and went to America. Then all of a sudden he was offered Hercules movies!"
Schwarzenegger made his acting debut in 1970 movie Hercules in New York but shot to worldwide fame playing the title character in Conan the Barbarian in 1982.
He added: "I thought, 'Well, this is exactly what I would like to do'. He trained five hours a day, so I started training five hours a day. Whatever he did, I did. I basically had the blueprint for what I had always dreamed about."
Watch the trailer for Arnold Schwarzenegger's The Last Stand below: