Begin the setup of this exercise by placing two dumbbells on one side of a flat bench. Kneel down on your knees and face the flat bench, with the dumbbells in front of your body. Grab both of the dumbbells with your palms facing upwards (this is called a supinated grip) and bring them up so that your forearms are resting on the flat bench with your wrists hanging slightly beyond the end of the bench. Begin the exercise by curling your wrists upwards. Once you have curled the weights as high as you possibly can, hold the peak contraction briefly before slowly lowering your wrists back down to the starting position. Ensure that, throughout this exercise, you are not moving your forearms or any other part of your body. Repeat for the prescribed number of repetitions.
One variation of this exercise involved using a barbell instead of dumbbells.