STARTING POSITION:
Select the appropriate weight of the dumbbells. Lie back on a fitball moving your arms to hold the dumbbells with a neutral grip just above you with your elbows slightly bent. Your trunk should be parallel to the floor. Retract your shoulder blades rising your chest up.
MOVEMENT:
Start lowering the dumbbells only moving the forearms until the dumbbells almost touches your forehead while you inhale. Return to the starting position in a strong movement by extending your arms while you exhale.
TIPS: While your are doing the exercise, move only the elbows joint, make sure you don't move any other part of your body. If you are a beginner at this exercise, use a spotter. If no spotter is available, then be conservative with the load that you use. Make sure your shoulder blades are always retracted.