A flat dumbbell press, also known as a flat bench dumbbell press, is a compound free weightlifting exercise. It primarily works the chest muscles, although it also provides a substantial benefit to the triceps and shoulder muscles. A flat dumbbell press requires the athlete to lie flat on his or her back while holding a set of dumbbells above the body, then to lower those dumbbells toward the chest before pushing them back to the starting position.
In order to perform a flat dumbbell press, an athlete must first lie face up on a weight training bench. The bench should be a standard bench that is parallel to the floor. Throughout the exercise, the head, shoulders, back and hips should remain on the bench at all times — there should be very little arch in the back, and the head should not lift. The athlete should bend the knees, and the feet should rest either on the floor or, less commonly, on the bench itself. This latter variation can make it more difficult to maintain balance during the exercise, though, so only experienced athletes should attempt it.
After the athlete is in position on the bench, he or she should arrange the weights into the correct starting position. The athlete should grip the set of dumbbells using a pronated grip. At the beginning of the exercise, the athlete's arms will be bent so that the weights are resting at or just above the level of the chest. The elbows should dip slightly below the body.
To perform the exercise, the athlete then uses the chest and triceps muscles to straighten the arms. This will cause the arms to push to the weights away from the body until, eventually, the arms are completely straight. The athlete should exhale during this motion. After completely straightening the arms, the athlete bends the arms again, inhales, then begins to lower the weight back to the original starting position while gently exhaling. The athlete can then perform as many repetitions of the flat dumbbell press as he or she desires.
In addition to varying the position of the feet, an athlete also can vary the position of the hands during a flat dumbbell press. If the athlete rotates the standard grip 90 degrees before performing the flat dumbbell press, the exercise will engage the arm muscles in a slightly different way. This will provide a slightly different workout.