1 Using an underhand grip, take hold of the barbell with your hands a few inches apart. Sit on the end of a bench, keep your back flat while resting your forearms on it but making sure that your wrist and hand hang off the end.

2 Allow your wrists to bend back and the barbell to roll to the ends of your fingers. Close your fingertips as you curl your palms toward your biceps.

3 Pause, reverse the motion, and let the bar roll back to your fingertips.