This exercise will mainly work the quadriceps, but will also work the glutes, hamstrings, and a little bit of calves. This exercise is done the same as a normal front squat except you only go down half way, which allows you to use heavier weights.
This exercise should either be done in a squat rack or you should have a spotter for safety reasons. Begin this exercise by placing the bar on a rack that is just below shoulder height. Next, bring your arms underneath the bar, cross them, and then grab the bar with both hands. The bar should be resting on your shoulders, while you keep your elbows as high as possible. Next, lift the bar out of the rack with your legs. . Step back into the squat position, and begin to squat. Begin by pushing your hips back and squatting through your knees, make sure to sit back into the squat. Continue to squat down until your thighs are halfway to parallel with the floor. Now, push through your heels and raise the bar by straightening your legs until you are back in the starting position. Repeat for the amount of reps you would like to complete. Finally, step forward and place the bar on the racks.
This exercise should not be done until you have mastered a full front squat. Make sure to keep your elbows high, this will be more difficult with heavier weights. Partial reps can also help to strengthen tendons, so it is a good idea to do them.