HOW TO DO IT: Sit on bench holding a dumbbell between your feet. Place the back of your upper arm on your Inner thigh. Lean into your leg to raise your elbow slightly. Curl the dumbbell up to the front of your shoulder. Lower the dumbbell back down to the starting position, until your arm is fully extended.
FORM TIP: When your elbows are fully flexed they can travel forward slightly, allowing your forearms to be no more than vertical.