Lock feet in, with pad comfortably on hips. Cross arms over chest. If using weight, hold weight plate at chest level. Pressing hips into the pad, relax the spine. Squeeze together (retract) shoulder blades. In a controlled motion, lift head and shoulders up until spine is comfortably hyperextended. Avoid hyperextending the neck. Maintaining controlled motion, return to starting position. Do not allow muscles to relax before next repetition.
Here are a few suggested alternative exercises:Back Extension - MachineBall Rise and ShineDumbbell DeadliftDumbbell Good Mornings