Bruce of L.A. (Bruce Bellas) is a very popular muscle photographer from America who shot during the 50's and 60's. I have a collection of his original work. There were other photographers who also followed the sport but he is my favorite. here is a link to a site which sells some of his images.
the largest collection of originals of his work that i know of outside his estate is kept at the Division of Rare and Manuscript Collections Cornell University Library in America. he is revered as one of the most important photographers in the history of American male Physiques.
here is a link to his website.