Stand upright with your hands by the side of your body with palms facing inwards, holding one dumbbell in each hand with a neutral grip.
Keeping your upper arms by your side, exhale and raise the dumbbells up towards your shoulders by flexing your arms and simultaneously rotating your palms outward. Avoid using your legs or back.
Continue until your arms are fully flexed and the dumbbells cannot be curled any further.
Inhale and lower the dumbbells down, returning to the starting position.