How to Do a Reverse Fly
A reverse fly is a great exercise for defining the backs of the shoulders. For this shoulder exercise, you'll need dumbbells and a stability ball.
Assume start position as shown by sitting on ball; lean your chest over your legs.
Weights should start comfortably at the sides of your calves, palms facing back.
Bring weights out to sides up to shoulder height and squeeze shoulder blades together.
Return to start position.