Not that many people consider Edward Norton as a muscular guy. That is, until his role as Derek Vinyard in American history X. This role demanded a muscular guy who looked like he fit well in prison.
Although Edward Norton isnt totally ripped in this film, he is impressively bulked up and very muscular in his overall appearance. This fit well with the central characters description, as he was not supposed to be an extraordinarily athletic person, just a muscle bound goon with racist tendencies.

Now how did Edward Norton achieve this physique?
Since Edward is a naturally slim guy, the first order of the day was to change his diet to include a high dosage of protein and carbs. He also had to increase his caloric intake to perform the workout he had to undergo on a daily basis per week.

The goal is to add 20 lbs of muscle to his 180 lbs frame.
To give him a formidable chest, Norton performed heavy sets with low reps of chest presses. This increased his chest size as well as developed his inner pecs to create muscle definition.

To enhance his shoulders, traps and deltoids appearance, Norton performed a variety of presses most notably the military press.
To provide a stronger core and back muscles, Edward performed back hyperextensions with heavy weights, which resulted in a defined back musculature. After that he would perform crunches and sit-ups to further develop his abdominal muscles. To enhance his love handles, Norton also performed side bends forcing each side to develop a leaner and more defined look.

All of these upper and mid body exercises were then complemented with squats to enhance his lower body as well. Since Derek Vinyard was supposed to be a very good basketball player, Norton had to develop an impressive pair of legs with muscle definition originating from his upper thighs down to well sculpted calves. Leg raises and standing calf raises helped him to achieve this.

To create a tapered V shape and to add over-all strength to his body, Norton performed weighted pull-ups and chin-ups. This basically meant he had a heavy plate tied around his waist to provide more resistance as he cleared the bar.
Each day of training started and ended with a cardio workout. Since he wasnt putting on too much bulk, Norton had no fear of engaging in this exercise and was able to maintain a fit and muscular figure which showed great results on screen!