Pumping Iron is a 1977 American docudrama about the world of professional bodybuilding, with a focus on the 1975 IFBB Mr. Universe and 1975 Mr. Olympia competitions. Directed by George Butler and Robert Fiore and edited by Geof Bartz and Larry Silk, it is inspired by the 1974 book of the same name by photographer Butler and writer Charles Gaines and nominally centers on the competition between Arnold Schwarzenegger and one of his primary competitors for the title of Mr. Olympia, Lou Ferrigno. The film also features segments on bodybuilders Franco Columbu and Mike Katz, in addition to appearances by Ken Waller, Ed Corney, Serge Nubret, and other famous bodybuilders of the era.

Shot during the 100 days leading up to the Mr. Universe and Mr. Olympia competitions and during the competitions themselves, the filmmakers ran out of funds to finish production and it stalled for two years. Ultimately, Schwarzenegger and other bodybuilders featured in the film helped raise funds to complete production, and it was released in 1977. The film became a box office success, making Schwarzenegger a household name. The film also served to popularize the culture of bodybuilding, which was somewhat niche at the time, and helped inspire the fitness craze of the 1980s; following the film's release, there was a marked increase in the number of commercial gyms in the U.S.

The film was released on CED and VHS, and then re-released on DVD in 2003 for the 25th anniversary of the theatrical debut. The film inspired three sequels: George Butler's Pumping Iron II: The Women (1985), a documentary about the world of female bodybuilding; David and Scott McVeigh's Raw Iron (2002), a documentary about the making of Pumping Iron and how the film affected the lives of those who appeared in it; and Vlad Yudin's Generation Iron (2013), a documentary on which Pumping Iron producer Jerome Gary served as executive producer.