Unlike a regular split squat where you attempt to push close to half of the weight load with the back/rear leg, to do the Bulgarian split squat you use the rear leg only for balance as the forward leg does the bulk of the work. To do this exercise, you can use a barbell for added weight and control or work without it. If you use the barbell, place it on the front of your shoulders like you are going to do a front squat or behind your neck, while placing one foot well out in front of the other in a staggered position with your rear foot placed firmly on top of a bench or box no higher than 18″. Make sure that you set your core and maintain an erect torso as you lower your body as deep as possible into the squat, while keeping your front heel firmly on the floor throughout the movement. As you begin to rise upward, exhale as you pass the halfway point during the ascent. Complete all the reps with one leg, then switch to the other to complete the same number of reps on the other side.