Leg Press: A Good (Auxiliary) Exercise (If Done Properly)

Trainers often tout the leg press as a safe alternative to squats, if one has injury prone knees or back.  However, squats can be beneficial for bad knees, provided they are done properly, and avoiding errors of form and execution.  That said, there are certain injuries, such as injuries to the back and hips, that may preclude you from squatting for a while.  Two popular alternatives are the hack squat, and the leg press.

Why the Leg Press is Popular

Simply put, it makes people feel strong.  Relative to squats or deadlifts, you can use a lot of weight.  This is true for two main reasons:

• On this machine, the weight moves at a fixed path.  You are not required to utilize muscles to stabilize and control the weight, like you do on a squat.
• MOST leg presses are built at a 45 degree angle.  This enables the lifter to use even more weight than pressing a weight perpendicular to the floor.

The other reasons leg presses are popular is that they do not tire people out the same way squats do.  Additionally, people "feel" safer using them.  Partially because of some of the falsehoods they have been told about squats, and the fact that putting a heavy weight on your shoulders can be a bit intimidating.

 A woman using a 45 degree inclined leg press.

Author Original uploader: SlimVirgin, under the Creative Commons Attribution-Share Alike 3.0 Unported license.

 http://commons.wikimedia.org/wiki/File:Leg_press_%28cropped,_flipped%29.jpg

Key Points to Remember

• Leg presses, like any other exercise, can cause injury if performed improperly.  No exercise is truly injury-proof.
• If you use a vertical leg press instead of a 45 degree press, be sure to drop the weight to about 70% of what you would use on the incline press.
• Wearing knee wraps is not advisable.  They are an aid to springing and bouncing at the bottom of the lift.  They pick up some of the stress that would otherwise be applied to your tendon, and your tendons will not develop with your muscle.  Long term use of knee wraps can cause patellar tendonitis.
• There is no exact substitute for the squat.  This rule applies to leg presses as well.  This exercise can serve as an auxiliary, or a temporary substitute if you have an injury that prevents you from doing squats.

How to Perform the Movement

Sit in the seat, or if you are using a vertical press, lay down under the platform.  When placing your feet on the platform, be sure to not place them either too high or too low.  If you put your feet too low, your glutes and hamstrings will not be sufficiently activated during the movement.  If you place them too high, your thighs will make contact with your chest at the bottom of the movement before your legs are able to bend to a sufficient range of motion.  If you have never done the leg press before, do a practice set with light weight to make sure you are activating both sides of your thighs.

Push off and use the knob near the handles to move the safety catch away.  Lower the weight not in a slow, but in a controlled manner until your thighs make contact with your chest.  Do not bounce your legs off your chest, and do not "bury" your thighs into your chest.  Moving them that far in can cause your butt to lift off the platform, and that puts incredible strain on the spine and hips.  Keep your buttocks in contact with the seat at all times.

Make sure you are gripping the handles; do not cross your arms in front of you, nor use them to push on your legs while performing the set; unless an emergency happens where you are in danger of not getting the weight back up.  Gripping the handles will help keep your butt and hips in place.

Use a weight that you can do for around ten repetitions before you fatigue.  Most leg press machines have a two pronged safety catch; one for racking the weight in the top position after the set is complete, and a lower prong in case you are unable to press the weight all the way back up.  However, this catch is not danger proof, when you are at the bottom of the movement, the sled will be below the lower prong.  Therefore, never go to absolute failure; the heavy weight you will use for a leg pres can trap and seriously injure you if you get stuck at the bottom of the movement.

Do not lock out your legs at the top of the movement, as it puts a lot of compressive strain on the knee joints.  Bring the leg to a near straight position, and when you have completed the set, push the sled past the point of the top safety catch, use the lever near the grippers again to bring the catch into the lock position, and carefully lower the weight down.