As with any exercise, proper posture and positioning ensures that you get the most out of the exercise and you can avoid getting hurt. The dumbbell row exercise has two variations -- the bent-over version and the upright version; both which have their own set of requirements for maintaining proper posture.
Bent-Over Row Movement
To perform the bent-over row, place one knee on a bench, with your shin resting along the top of the bench. Then bend forward with one arm supporting you on the bench. The arm should be up or down along the bench -- whatever allows you to maintain a flat back parallel with the floor. Position your dumbbell on the floor just below the outside shoulder, and then lean down to pick it up. Start the exercise with the outside hand -- the one now holding the dumbbell -- straight down, perpendicular to the floor. Bend the elbow as you "row" the dumbbell upward toward the ribs, stopping when the top of the upper arm is parallel with the floor.
What to Watch
Maintain a strong, flat back and engage your core muscles to avoid arching the back during the bent-over row. Your torso should be as parallel to the floor as possible. As you move the dumbbell from its "down" position to its "up" position, avoid twisting your torso. As you do the rowing motion, do not "throw" your arm upward, as this could do damage to your lower back. You won't always be able to see whether you're doing these exercises correctly, so ask a trainer at a gym to check your form.
Upright Row Movement
For the upright row, stand with a dumbbell in one hand and place your feet shoulder-width apart. With your free hand, grasp a doorway, wall or another stable structure. Allow the arm with the dumbbell to rest in front of its corresponding hip, with your palm facing inward. Then pull the dumbbell upward and bend the elbow, stopping the dumbbell when its just in front of the armpit. You'll need to bend your wrist a bit to allow for the movement of the dumbbell.
What to Watch
As you do the upright row, brace your core to keep your back from arching backward. Also watch the placement of the elbow of the arm doing the lifting; it should be pointed to the side and not pointed forward. If you point your elbow toward the front, you run the risk of doing damage to the shoulder's tendon and bursa -- the protective sac between the bone and tendon. As with any exercise, keep your shoulders back and your chest up to prevent injury.
Nicole Vulcan has been a journalist since 1997, covering parenting and fitness for The Oregonian, careers for CareerAddict, and travel, gardening and fitness for Black Hills Woman and other publications. Vulcan holds a Bachelor of Arts in English and journalism from the University of Minnesota. She's also a lifelong athlete and is pursuing certification as a personal trainer.