In an untrained lifter, deadlifts are a guaranteed 15 pounds of muscle mass. Think about it: you’re using your entire upper back, glutes, hamstrings, core musculature, and forearms. If you haven’t done anything with these muscles before, they’re going to get bigger quickly. Put 100 pounds on a newbie’s deadlift and you’ll bump him up a shirt size in no time. This principle can also be applied to experienced lifters who haven’t deadlifted in the past; leg curls just won’t get the job done to the same extent that heavy deadlifts and rack pulls will. For added upper back emphasis, try snatch grip versions.

Eric Cressey