"Sit and grasp bar with narrow to shoulder width underhand grip. Rest forearms on thighs with wrists just beyond knees.
Allow barbell to roll out of palms down to fingers. Raise barbell back up by gripping and pointing knuckles up as high as possible. Lower and repeat. "
http://exrx.net/WeightExercises/WristFlexors/BBWristCurl.html

Muscle group: Triceps

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