Dr Mel Siff Blog

.

A member wrote wrote:

< …..I think this BOX SQUAT exploration is interesting and assume (excuse
the pun if you see it) that most have not analyzed it completely.

There are many reasons that those who use this squat are able to handle such
enormous weights. I mentioned that I thought the action/reaction sequence of
the compression and expansion of the hams and gluteals against the unyielding
surface of the box was more of a factor than most perceived at the very start
of the action forwards and upwards.>

Dr Mel Siff: You may recall that we both discussed this issue some months ago on this
list, when I also stressed that the contact between adjacent soft tissue
surfaces can play a useful proprioceptive facilitation role. The box squatting
action
concerns not simply the hams and glutes, because the compression-expansion here
tends to
be more viscous and damping in nature than elastic (the contact time often is
too long
to permit significant elastic energy recovery and the mechanical stiffness of
the
posterior chain muscle complexes is too low in that situation) — there can be
an even more powerful contribution between the lower abdomen and the top of
the thighs, where pneumo-elastic recoil can be quite marked.

Member:

<I have also suggested that the “lever arm” of the femur is “in contact” with
the box at a shortened and more effective leverage position during the
initial “push off” stage. This too is a substantial contributor to being
able to handle “larger” loads. An example might be if you imagine squatting
by holding the bar (in your hands) on your thigh at “hip joint” level. Then
imagine squatting again, but this time moving the bar down to just above your
knee. Which squat would be easier? In the box squat, the initial leverage
is more favorable.

Dr Mel Siff:  This is not a valid analogy – by moving the bar as you have described it,
you have changed the centre of mass of the combined bar-lifter system, not
simply shifted the fulcrum. For all list members who like challenges, try
drawing a “free body diagram” and see what that tells you about any comparison
between squatting in free space and squatting on a box. For anyone who would
like to carry out this biomechanics tutorial, go ahead and let me have your
feedback, if necessary sending me a JPG or PDF file of your resulting diagrams.

Dr Mel Siff
Denver, USA
http://groups.yahoo.com/group/Supertraining/

For more information on Facts and Fallacies of Fitness by Dr Mel Siff please click here

Tags: Box Squats, Centre Of Mass, Dr Mel Siff, Elastic Energy, Elastic Recoil, Energy Recovery, Lever Arm, Lifter, Lower Abdomen, Mel Siff, Proprioceptive, Reaction Sequence, Soft Tissue, Squats, Super Training, Supertraining, Tissue Surfaces