Arnold was known for his huge, peaked biceps. He was only 19 years old when he boasted 20-inch arms, so he knows his stuff. "Because muscles and arms are so closely related, it is not difficult to get yourself mentally involved into arm training," says Arnold.
He's quick to point out that a well-developed arm includes more than just bulging biceps, though. "They need to look good in a lot of poses and from a number of different angles," Arnold explains. "This means that every part of the arm muscles, every contour and angle, must be fully brought out. This takes a lot of thought and planning."
Fortunately, Arnold has done the leg work (arm work?) for you once again. Push yourself through his entire arm and shoulder workout, and you'll see the kind of results he's talking about.