Next to squats, the leg press is probably my favorite exercise for working the thighs (quadriceps and hamstrings). This exercise gets a lot of criticism from purists, but it is a legitimate, compound movement for building size and strength in your legs.
I learned one of my favorite variations of this exercise from none other than legendary powerlifter Ed Coan (so much for that theory of leg press only being used by weak wannabes). He mentioned single-legged presses (using only one leg at a time) as a useful assistance lift in one of his videos. According to the video, he got the idea from watching an amputee train.
Just keep this in mind: leg press can be really hard on your lower back, especially if done improperly. Remember this before you try to load up every plate in the gym.
I usually see two mistakes in the gym when it comes to this exercise:
*Not going deep enough with the reps. This is the main mistake I see–guys loading up the bar and doing “fourth reps.” If you are going to do the exercise, go ahead and go parallel. Check your ego at the door and do it right.
*Going too deep with reps. I mentioned that leg press can be hard on your lower back. If you go beyond parallel your rear end will naturally start to come up off the seat. This puts you at great risk for injuring the discs in your lower back. 90 degrees is enough–don’t try to bring your knees to your chest.
You can experiment with different foot placements for variety. Placing your feet higher on the platform will put more emphasis on the hamstring and glutes. A lower foot placement will tend to emphasize the quadriceps.
I mentioned that I usually do squats (or a variation such as front squats) then follow it up with leg pressing. Here’s why I like training this way: I find that my back often gets worn out before my legs with squats (especially standard barbell squats). Leg press allows me to keep safely training legs even when my back is fatigued.