Instructions:

1. Sit on a flat bench with a dumbbell in each hand, palms facing each other.
2. Raise the dumbbells to shoulder height, then rotate your wrists so that your palms are facing away from you.
3. Press the dumbbells up until your arms are fully extended, then lower them back down to shoulder height.
4. Rotate your wrists back to the starting position and repeat for the desired number of repetitions.