The Dumbbell Pullover is an effective isolation exercise that primarily targets the muscles of the upper body, including the chest, lats, and triceps. It involves lying on a bench and lowering a dumbbell backward over the head in a controlled arc motion, then returning it to the starting position. This movement stretches and contracts the chest and back muscles, promoting upper body strength and flexibility. Dumbbell Pullovers are beneficial for enhancing chest expansion, improving shoulder mobility, and contributing to overall upper body muscular development.