I am completely positively 100% sure. I have seen the original shots that were then photoshopped. I spent a while hunting for them again to post here, but now I can't find them! As I mentioned before, the artist left a watermark in his pics. Notice the "X" placed on Arnie's right elbow. Also the artist edited Arnold's hairline to give him a more receding MPB look. There was another pic which made him even fatter and half bald.
I heard Stallone used body doubles for the ab shots in some films In Arnold's biography it said he started using roids at 15, By 18 he was a Monster already
Finally found the original! Here it is, along with the edits which were made as an April Fool's Joke last year. Image Unavailable, Please Login