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 arm by your side, exhale and raise one dumbbell up towards your opposite shoulder by flexing your arm and maintaining a neutral grip. Avoid using your legs or back to lift the dumbbell.
Continue until your arm is fully flexed and the dumbbell cannot be curled any further.
Inhale and lower the dumbbell back down, returning to the starting position.