Sit on a stability ball with a dumbbell in each hand.
Roll down and out until your upper back is on the ball and your torso is parallel with the floor.
Raise the dumbbells up so that they are over your chest.
Firmly plant your feet on the floor for balance.
Bend your elbows a little, and internally rotate your shoulders so that your elbows point out to the sides.
Execution
Keeping a slight bend in your elbows, inhale as you lower the dumbbells out to your sides.
Exhale as you return the dumbbells to the starting position.
Repeat for the prescribed number of repetitions.
Comments and tips
The stability ball makes the typical dumbbell fly more challenging since the surface you are lying on is unstable. The instability forces the activation of several muscles, especially in your core.
Internally rotating your shoulders brings the origin and insertion of your pectoralis major into better alignment, thus better isolating the muscle.
To reduce pressure on your shoulders, arch your back and stick your chest out.
Only perform this exercise when you’ve mastered the form of the dumbbell fly.
