Safety Bar Bulgarian Split Squat
This is the most advanced variation and allows you to load more weight than any of the other movements because you're no longer limited by what you can hold. If your gym has one, set up a safety bar (specialty barbell with two handles that sit across the shoulders pointing out in front of the lifter) in a rack and a bench just behind the squat rack. Get setup under the safety bar and walk it out of the rack. Hold the squat rack with your hands (the safety bar will stay in place on your shoulders), and carefully place the back foot on the bench. From here, perform the squat as normal. Be very careful with this variation and only move on to this variation once you have mastered heavy dumbbells and kettlebells.