DESCRIPTIONStand with your feet shoulder width apart, slight bend in the knees, and abs tight. Hold a single dumbbell vertical, with both hands under the top plate, up over your head with arms straight up in the air.
Keeping your abs tight so you don't arch your back at any point in the movement, inhale as you bend your elbows to lower the dumbbell behind your head. Exhale and lift the dumbbell back up to the starting position, and be sure to keep your elbows pointed straight up towards the ceiling (don't let them point out to the sides) throughout the movement.
You may have to put your head forward slightly so you don't hit yourself with the dumbbell.