Starting Position: Stand with the feet shoulder width apart on the hack squat machine.
Performing The Exercise: Squat under the pads of the machine and extend up until the legs are straight. If required, unlock the safety pins from the machine, and bend at the knees, keeping the back against the pad of the machine. Lower down to a 90 degree angle and then slowly push back up to a fully extended position. Repeat this motion.
Tips: Make sure the machine platform is set so the ankles are in a neutral (90 degree) position. Avoid pushing up on the shoulder pads with the hands, this can lead to neck and shoulder injuries. Going below 90 degrees on these squats is unnecessary.