Dive into a pool. The water should be at the height of your neck. Stand straight with your feet shoulder width apart.
Raise your arms in front of you until they are parallel to the floor while you exhale. Return to the starting position in a strong movement while you inhale.TIPS: While your are doing the exercise, move only the arms, make sure you don't move any other part of your body. The exercise key is quality over quantity. The trick is to perform the exercise using proper form.