Holding a dumbbell in each hand with your closed palms facing out, stand with the knees slightly bent. Keep your back flat and bend forward at the hip joint.
Lift both arms to the sides, maintaining a slight bend in the elbows, and squeeze your shoulder blades together. Then, with control, lower the dumbbells back together.
This completes one rep.
Do 10 to 20 reps.
Bonus: this exercise strengthens your upper back to improve your posture.