Dumbbell Rear Lateral Raises
Seated on a bench bend forward with a dumbbell in each hand. Have your arms extended and elbows slightly bent.
Raise your dumbbells out to the sides and up to shoulder height. Focus on squeezing your shoulder blades together. Only raise your arms, not your upper body and keep your midsection firm throughout the movement. Slowly lower the dumbbells down again to starting position. And repeat.