The bent-over barbell row is a weightlifting exercise that works most of the muscles of the back. If you're just starting out, master good form with a light, pre-weighted barbell -- not the standard 45-pound Olympic bar you find on the squat rack. Use a weight that doesn't force you to round your low back and compromise form. What constitutes light depends on your fitness level, experience and genetic strength.
Goals for Lifting
Once you've mastered your form, choose weight specific to your strength-training goals. If you're lifting to maintain muscle and stay healthy, aim for a weight that's equal to 60 to 80 percent of your one-repetition maximum -- the most weight you can do with good form for a single repetition -- and do at least one set of eight to 12 repetitions. If you're looking to build size in your latissimus dorsi, trapezius and rhomboids, aim for heavier weight -- as much as 85 percent of your one-repetition maximum -- and do three to six sets of eight to 12 repetitions of the move. For enhanced strength, do just five or six repetitions in each of three to six sets with 88 percent of your one-repetition maximum.