This is a good exercise for the tricpes. Sit on a bench and hold a dumbbell with both hands by the end where the weight plate is, palms up, thumbs together, over your head. (Make sure that the weight plate is secure before you attempt this exercise. Idealy, you would only perform this exercise with pre-set weights.) Lower the weight behind your head by bending your elbows. Then bring it back up to the starting position.

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