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Dumbbell Eccentric Wrist Curl
1) Stand tall with the chest up, core tight, head neutral and back flat.
2) Grab the dumbbell with an overhand grip. Lift it up in front of you so your arm is vertical to the floor.
1) Use your right hand to rotate the dumbbell towards the ceiling. This will cause your palm to lift up.
2) Release your right hand and allow the dumbbell to drop forward. The endpoint should be a straight line between the arm and wrist - your palm now should be facing the floor.