sentences:  In addition to his outdoors writings, Gaines covered the "Golden Age" of professional bodybuilding and is the author of "Pumping Iron", considered the definitive journalistic work in that field, and credited in large part for bringing greater public awareness to what was formerly a little-known subculture, as well as helping to launch the career of Arnold Schwarzenegger.Gaines also narrated and contributed to the documentary film of the same name.Gaines is active in the conservation movement and in particular the stewardship of the North American Atlantic Salmon fisheries.