Begin by sitting on top of the Swiss ball with your feet flat on the floor and dumbbells to your sides, palms facing inwards. Lean over so your chest is slightly above your knees. This forward lean is what will work the muscles towards the back of your shoulders.
Raise your arms to your side, bringing the dumbbells up to shoulder level height. Keep your arms as straight as possible but do not lock your elbows. Slowly lower the dumbbells back to the starting position. Try doing 2 sets of 10-12 repetitions.
Keep spine in a neutral position and your head and eyes looking forward, not down.
Muscles Worked: Upper back
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