The 1930's were a time of political and economic upheaval, and they were also a transitional period for male nude photography. It was the dawn of the golden age of physique photography when bodybuilders (as opposed to strong men or athletes) moved to the forefront. Earle Forbes' work was indeed transitional, as shown in this photo of an unknown model.
Edited to add: Greggy sent a comment identifying this as Charles Whitlock, and that's correct.
He did some attributed work with Al Urban.