Dumbbell Bulgarian Split Squat

Start: With dumbbells in each hand, stand with one foot up on a bench or step behind you, and the other in lunge position. (Step out far enough so, when you lower yourself, your front leg will remain perpendicular to the floor.) Hold your torso upright. 
 
Finish: Lower yourself until your front thigh is parallel to the floor. Raise back up, and finish the set with that leg.