Just remember that Arnold didn't use the same training protocols throughout the year.
For the first four months of the year, he used a HIT protocol, training using either the whole body on one-day, or splitting it õp between upper body and lower body, using 2-3 sets per muscle group.
For the next four months he trained once a day, every day, training every bodypart once a week, using a 15-20 sets per muscle group.
For the final four months (pre-contest), he trained twice-a-day, hitting each bodypart twice a week, using 15-25 sets per muscle group.