HOW: Grab a bench or any elevated surface. Taking two steps away from the bench, set up in a split stance position facing away from the bench. Elevate the rear leg foot onto the bench, getting the contact point where the ankle hinges.
Keeping the chest tall, drop into the lunge position. Hold this position.
FEEL: You should feel the front and back quadriceps working.
COMPENSATION: Avoid letting the trunk bend forward. Avoid letting the front knee cave inward.