Place a barbell behind your neck as you would for a back squat while sitting with your legs straddling a bench, knees bent and feet flat on the floor in farther forward than your knees. Set your back tightly in a complete arch, locking it in position with tight abs. Hinge at the hip, maintaining the back arch, and bend forward as far as you can without losing the arch in the back. When you reach the bottom, reverse the motion, being sure to not let the arch soften, and return to the original upright position.
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