The dumbbell pullover is a compound exercise that targets both the chest and the back. This is one of the only exercises that works opposing muscle groups at the same time. The movement involves holding a dumbbell directly overhead, so start with a light weight and work your way up after you become comfortable with the exercise.
The Basic Movement
Sit on a flat weight bench, facing out to the side and holding a dumbbell in both hands. Walk your feet forward and lower your upper body onto the bench. Rest your upper back and shoulders on the bench. Your hips should hang off the edge and be slightly lower than the bench. Place your hands, palms up, around one end of the dumbbell. Hold the dumbbell directly over your head and lock your arms in a slight bend. Inhale and lower the dumbbell in an arc behind your head until you feel a stretch in your chest. Return to the starting position.
The main movers during the dumbbell pullover are the chest and back. Your latissimus dorsi, the largest muscles of your back, initiate the pulling movement when the dumbbell is at its lowest point. Your chest muscles take over at the end of the movement, as your arms become perpendicular to the floor. Several other muscles assist during this exercise including your triceps, rear shoulder muscles and rhomboids.
Try a Few Variations
For an easier version of the dumbbell pullover, lie supine along the length of the bench instead of hanging off the side. You don't get as much of a stretch at the bottom of the movement, but you don't have to worry about your hip position.
You can also do pullovers with other fitness equipment including a barbell, cable machine, resistance band or medicine ball.
Things to Keep in Mind
Do not use adjustable dumbbells for this exercise. If the collar is not tight, the weight plates could slide off and hit you in the face. For the same reason, only use dumbbells that are in good condition for this exercise.
Your shoulder flexibility limits the range of motion on the dumbbell pullover. Do not force the dumbbell lower than is comfortable, or you could injure your shoulders.