Set up on the hack squat machine by placing your feet mid-level on the platform. Your feet should be close together (but not touching) and your shoulders braced up on the shoulder pads. Get ready to unlock the safety mechanism to start the initial squat. This is your starting position.
Unlock the safety and grab both handles with your hands and squat down all the way until your legs are bent past a 90-degree angle. Make sure that when you squat down your knees don't go past your toe line (if they do adjust your footing by placing your feet higher on the platform). Then, push back up all the way until your legs are almost straight. You should always keep tension in your legs for optimum movement efficiency.
Finally, repeat entire movement for the desired or prescribed number of repetitions.
Perform this exercise in a smooth and fluid motion
Keep your head up straight; don't look down at your feet as this will strain your neck muscles
Don't extended your legs completely on the downward portion of the movement
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, slow down the movement or increase the weight.
This is an excellent exercise for your calves. It's very comfortable to execute because of the smooth guided motion of the hack machine. The narrow-stance combined with the angle of your body make this exercise very unique in how it "hits" your calf muscles.
The only disadvantage to this exercise is not the exercise itself, but the machine on which it is performed on. In our experience, most fitness centers will not invest in purchasing a hack machine unless the gym is a serious bodybuilder's type of gym. These machines tend to be expensive and are not used as much as other machines which makes them cost-ineffective.