Stop searching. Start lifting. And remember Arnold’s closing line: "I’m going to do something that’ll baffle everyone... I’m going to go into movies." You can watch the birth of that dream by securing your legal download today. Have you legally downloaded Pumping Iron? Which scene motivated you to hit the gym? Share your thoughts in the comments below. And for more classic fitness documentaries, check out our guides on Stay Hungry and The Perfect Physique.

Go to Amazon.com, search "Pumping Iron digital rental," and click "Buy." For the budget-conscious, set a free alert on JustWatch.com for when it returns to Netflix or Hulu.

Pumping Iron blurs the line between documentary and narrative. Director George Butler and editor Robert Fiore captured a moment when bodybuilding was shifting from a fringe activity to a mainstream spectacle. Arnold Schwarzenegger, already a five-time Mr. Olympia, is the anti-hero who admits to "psyching out" competitors. Lou Ferrigno, fresh off his Incredible Hulk casting, is the earnest underdog pushed by his domineering father.