Hattori recommended this move to work your shoulders and arms. Key tip: keep your core tight and avoid arching your back.
- Start standing with your feet shoulders-width apart and a slight bend in your knees. Hold the dumbbells down at your sides, palms facing towards each other.
- Turn your hands so your palms face up. Bring the weights to your shoulders, performing a bicep curl while keeping your core tight and your back flat (not arched).
- With the dumbbells held at shoulder-level, turn your palms to face outward.
- Straighten your arms to press the dumbbells overhead, extending until your arms are straight (but don't lock your elbows).
- Bend your elbows, lowering the dumbbells back to your shoulders. Turn your hands so your palms face your body as you lower them.
- Lower the dumbbells to your sides, completing the bicep curl movement.
- Turn your palms towards each other again as you come back to the starting position.
- This counts as one rep.