Coach Alicia Fong

Just another weblog

Health tip for week Oct. 19th

  • Avoid doing leg press because it’s dangerous.

Doing leg press machine is not only really bad for you but also not functional.  The leg press is when you sit on the machine at a 45 degree with your back against a pad and your feet on a platform.  You push the platform until your legs are straight and lower the platform by bending your knees again.

leg_pressWhy is bad?

  1. It is dangerous on your lower back.  We need mobility in certain areas of our bodies and we don’t need that in our lower back.  We need stable lower back.  If the hips do not move properly, our low back eventually will hurt.  Dr. Stuart McGill, a low back specialist, states that “any flexion or extension will create a disc to blow.”  It might not happen the 1st, 2nd, or 50th time you perform this exercise, but eventually your low back will “hurt”.  A physiologist, Dr. Michael Yessis, also concurs that the potential danger in this exercise is seen when you, in an attempt to get a greater range of motion, bring the knees in close to the chest on the lowering phase. This, in turn, rounds the lumbar spine and because of the heavy weights typically used, the pressure acting on the spinal discs increases greatly. The high compression forces can cause disc rupture or other low back injury.
  2. The exercise is a completely nonfunctional movement.  Where in real life do you have to push out with your feet to move a heavy object and your back is locked at a 45 degree?  It’s more likely that we are standing on the ground lifting a heavy object, pushing ourselves off the floor (in other words, jumping off the floor), and/or squatting and carrying a heavy object.  There are many other situations but not one leg press movement will imitate any movements that are actually useful in real life.
  3. It causes knee pain and increase injuries in the future.  When you are in a sitting position and pushing heavy weights with your leg, you are strengthening lower body muscles but not teaching certain muscles to stabilize your body.  Muscles have more than one function.  In this situation, your gluteus (butt or glutes) muscle, for instance, will shut down.  There is no way you will fire up those glutes while sitting down.  One big function of the glutes is to stabilize the hip and the hip stabilizes your knees.   So, the leg press causes a neurological dysfunction in your lower body.  Also, the fix position you are forced to be when doing the leg press will cause degeneration and weariness in your knees.  Every time you do a rep in the leg press machine, you are in a fixed range of motion.  The machine fixes you and forces you to do the same exact mechanics/movements in your knees all of the time; therefore, degenerating and wearing out your knees.  While doing squats, the knees always bent slightly different every time and move accordingly to how your body is built.

Recommendation: Do squat instead of leg press.  First, doing leg press is easy.  People love to load up the machine with lots of plate and then say they lifted heavy.  If any of these people could squat even half of what they use in the machine, I would be impressed.  “You get to lift a whole lot of weight without actually accomplishing anything here”, a friend told me this once and it applies here for leg press.  A squat offers all the benefits but a fraction of the dangers.  If you have existing lower-back problems, customize your squat. There are so many different types of squats, find the one that is appropriate and functional to you.  Ask a trainer if you don’t know which ones to do.  The body is meant to function in a certain way so let’s train it the way it needs to be trained.

October 20, 2009 Posted by | Uncategorized | , , , | Leave a comment