http://AskTheTrainer.com/best-leg-exercises.html Personal Trainer Michael Behnken, MS, NASM-CPT-PES, CSCS The barbell hack squat is far superior to the hack squat machine. The hack squat is safer than the dead lift because there is less tenancy for your back to round and shoulders to protract because the bar is behind your body. The weight you can use for a hack squat is almost identical to the dead lift. http://AskTheTrainer.com