Superman (Salkind films) adopted a high protein diet. He added of muscle to his thin frame. He later made even higher gains for "Superman III" (1983), though for "" (1987), he decided it would be healthier to focus more on cardiovascular workouts. One of the reasons Reeve could not work out as much for "" was an emergency appendectomy he had in June 1986. Reeve was never a Superman or comic book fan, though he had watched "Adventures of Superman" starring George Reeves. Reeve found the role offered a suitable challenge because it was a dual role. He said, "there must be some
Superman with superhuman powers. The Nazis also thought Superman was a Jew and in 1940 Joseph Goebbels publicly denounced Superman and his creator Jerry Siegel. However, the historian Martin Lund argues that the evidence for Jewish influence is circumstantial, and notes that Jerry Siegel was not a practicing Jew and that he never acknowledged the influence of Judaism in any memoir or interview. Superman stories have occasionally exhibited Christian themes as well. Screenwriter Tom Mankiewicz consciously made Superman an allegory for Christ in the 1978 movie starring Christopher Reeve: baby Kal-El's ship resembles the Star of Bethlehem, and Jor-El gives his