Shoulder W raise in prone with weighted ball (Scapular retraction stabilization, prone-L, lifting arms, with weight, palms neutral)

Lie on your front with your forehead rested on a small towel.
Hold a weighted ball in each hand.
Keeping them straight, move your arms out to your sides then bend each elbow to a right angle.
Your arms should each make an "L" shape.
Your palms should face in towards one another.
Keeping your chest and head in contact with the floor throughout, squeeze your shoulder blades together, and then lift your arms off the floor.
Hold this position.
Relax and repeat