Schwarzenegger had a unique physique with a natural flow and good overall aesthetics. In the 1970s he fit in the category of mass monster. Bodybuilders of that era like Serge Nubret and Frank Zane competed at lower body weights and were considered more aesthetic. One of the features aesthetic bodybuilders tend to have is straight shoulders whereas Arnold’s tend to slope or hang. This type of shoulder structure did not detract at all from his physique. It’s not a negative, it’s just different. This non-posed, relaxed shot underlines the massiveness of Arnold’s back. Even though he didn’t do a lot of rear lat spreads he was no slouch in the back department and even had a striated “Christmas Tree Back” way back in the 1970s.