Dumbbell pectoral fly, which is also known as chest fly, is a particular exercise for upper body muscles. It is an isolation move that only involves pectoral or chest muscle but using a stability ball involves the core abdominal muscles also. It is an effective way to work on major chest muscles and focus the outer part of the chest to make it strong. Dumbbell pectoral fly involves in the movement of shoulder joints as well while not moving the elbows. Using stability ball takes the workout on a more challenging level. Lying on stability ball involves core abdominal muscles in the workout while targeting the upper pectoral muscles. It helps you improving range of motion and shaping your chest muscles. It increases your balance, stability and coordination.