A hack squat machine places the user in a reclined position with shoulders under pads, guiding the body through a fixed squatting path. The design emphasizes the quadriceps while minimizing lower-back involvement. It allows heavy loading with a stable, supported torso. Adjustable foot platform positions shift the emphasis between the quads, glutes, and hamstrings. It is a favorite among bodybuilders for building leg mass and strength. Because the back is supported, users can push closer to failure with less risk. The machine is also useful for athletes who want to improve lower-body power without excessive spinal loading.