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Deejay_Spike

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SQUATS AND MYTHS (1995)

Dr Mel C Siff
School of Mechanical Engineering
University of the Witwatersrand, South Africa

My comments on squatting technique have drawn a mixed bag of agreement and
upset, which is always the case with fundamental exercises which tend to be
surrounded by years of superstitious application.

GENERAL COMMENTS

Rest assured that this type of analysis is not meant to belittle. Heaven
knows how many times we are all challenged at lectures, conferences and
lifting platform about the appropriateness of our technique. I thank those
who have chosen not to be politically correct and kind to me over the years,
otherwise I would have been happily contented with the same old myths
forever.

Argumentation, analysis, refutation, rebuttal and counterproposal are all
time-tested ways of research and teaching. Regrettably we often feel that if
someone attacks ideas we believe in, then we are being personally attacked.
Most of the time we did not even create the offending idea, yet we have used
it so often that we become emotionally attached to it. In the case of
religion, politics and coïtus, criticism invariably leads to such passionate
encounters that even families become split up and nations go to war. Even
science is not immune to this belief fervor - just try to argue about
evolution and you will see what I mean.

In the world of fitness, a similar scene rules and it is inordinately easy to
tread on toes. The one merit of the Internet is that everyone can attend
(unlike some costly conferences and some forbidding lecturers) and become
involved and for that we thank fellow list member, Pansy. She prodded all of
us into a series of encounters from which we will all emerge enriched, if
personality clashes do not cloud the content. So, those of us such as myself
who have analyzed your comments in some depth still appreciate your
willingness to become involved.

SOME SPECIFICS

That having been said, it is still essential to comment on one of the worst
beliefs that one encounters at virtually every fitness convention and in
every popular publication, namely:

"This exercise is for the average person or beginner and is not meant for
athletes or experts"

While the sentiments are well founded, they often tend to insult the
'average' person - who on earth always wants to be just 'average'? None of my
clients wants to stay 'average' or 'novice' - that's why they are visiting a
professional - they want to move out of averages and progress to something
far greater.

Of course, we start with carefully graded sequences of exercises, beginning
with no added loading, and then progress cyclically to greater heights to
achieve mutually agreed-upon goals, but we must never lose sight of the fact
that any beginner HAS to be moving progressively onto significant resistance
(or duration, degree of difficulty, range of movement etc.) - and this is
where the problems begin.

Research has shown that skills developed with minimal loading do not
necessarily transfer effectively and safely to situations with greater
loading. Moreover, learning a skill using movements which are similar to, but
not the same as the actual exercise being taught, causes the same sort of
motor problem, because the controlling program being instilled into the
central nervous system is different for every different variant or pattern of
movement.

Thus learning of the half squat, power clean or machine bench press does not
properly prepare the beginner for safety and efficiency with heavier loads.
In fact, the well-meaning, but misguided advice to do certain 'safe'
movements can actually lead to the dangerous situation in which the client
may be MORE vulnerable to injury if he/she by chance is called upon to
execute the banned form of that exercise.

ADAPTATION AND OVERDESIGN

Just as one overdesigns roads and buildings with a greater "Safety Factor"
than 1 to withstand greater loads in earthquake zones such as San Francisco,
so we should overdesign the body just in case it is sometimes called upon to
do that dread activity that all the fitness authorities cautioned us against.

So we have to teach, modify or relearn the skill each time we are exposed to
some noticeable change in its characteristics, such as degree of resistance,
range, speed, duration and pattern. If one is likely to be exposed to fatigue
with an exercise, then we have to ensure that the client knows the different
skills of learning and coping under conditions of fatigue. It is highly
misleading to believe that there is only one specific skill for a given
exercise at a given time for every single person.

It is also misleading to lump all squats together. Even though they all
involve knee, hip and spinal actions, the powerlifting and weightlifting or
deep-knee bend squats differ very significantly in execution and distribution
of forces through range of movement.

There tends to be an irrational fear associated with deeper-than-parallel
squats, even though most of this is based on theoretical analysis and is
usually contradicted by clinical studies which show that even more knee
injuries occur in activities which do not flex the knee anywhere near
parallel (such as running and jumping). Others show that partial squats can
traumatize the knees even more than full squats!

Do the critics not appreciate that full squats executed under appropriate
control throughout the movement actually produce adaptation (that is what all
training is about, anyway!), enhanced strength, better stability and greater
resistance to unexpected loading? That is what the principle of Gradual
Progressive Overload is about, isn't it?

THE REAL DANGERS

The sooner folk realize that safety of execution does not depend primarily on
the exercise alone, but the technique with which it is executed. Thus, a full
squat executed slowly over full range may produce smaller patellar tendon
forces than a part-range squat done a bit more rapidly. As a matter of fact,
the patellar tendon force is frequently much greater during step aerobics,
running, jumping, kicking and swimming than during controlled full squats
with a load even exceeding twice bodymass.

The dangers of a squat (even a part-range one) lie more in inward rotation of
the knees, unequal thrusting with one leg, loss of stability with fatigue or
poor concentration, unskilled use of ballistic action or the use of some
object to raise the heels and increase the stress on the patella and its
tendon.

Does this mean that we should then advise against all these activities? Of
course not! If we presented a table of the stresses and strains acting on all
the tissues of the body during apparently innocuous daily activities
(including the pressure in smaller blood vessels subjected to the pumping
pressure of the heart), we would never get out of bed.

Sorry, these arguments of great forces and stresses and so forth have to be
looked at in context - the body grows, adapts and flourishes in response to
an optimal level of regularly imposed stress. It is also misleading to talk
about forces and tensions being large, because we should only do so in the
context of knowing something about how big, strong and dense the tissues are
upon which they are acting.

If the tendon has a large cross-sectional area and the connective tissue
comprising it is strong and extensible, then we have far less to worry about
than if the tendons were not like that. Remember that a knowledge of the
STRESS (force averaged over the cross-sectional area of the tissue) and
STRAIN (how much the tissues lengthen relative to their original length) is
far more relevant than the force itself. Forget about forces being quoted out
of context - we have to be far more specific than that before we can condemn
some poor exercise to death.
 
part 2

SOME DISCUSSION OF DISAGREEMENTS

GENERAL

< Like I said above, at no time did I suggest this was appropriate for actual
training but was trying to create an idea of overall form. When did I ever
say "significant weight" or bouncing or doing it fast? Remember my objective
was to help in form, in bodily placement, not in an actual weight training
program . >

***EVERYTHING is part of training and appropriate or inappropriate for
training. My comments about overall form are answered by my analysis of how
much the skills of execution vary all the time and that beginner methods may
not necessarily be enough to ensure that efficiency and safety continue to
reign. In terms of the two criteria applied to problem-solving situations,
those initial drills may be NECESSARY, but they are not SUFFICIENT for
learning squats which gradually increase in degree of difficulty (even if the
difficulty is because one is growing older and weaker!)

If the next response is that the client is never going to add a load and
remain at the same level and number of reps, I must say no more and go my way
in peace. But if progressive increase in fitness is the aim, well, all the
preceding commentary remains relevant.

placement not an actual training routine. >

***Another little problem lurks in this comment. It is commonly believed that
adding an external load is the only way to produce really significant loads
on the joints and tissues. This myth has beset resistance training for
decades and many coaches and doctors still believe that non-load bearing
exercise has to be safer than load-bearing exercise.

If we wander back to Newton's 2nd Law (Force F = Mass x Acceleration), we
learn that the force may be increased either by adding load or by
accelerating the action. In fact, since it is easier to move faster or
accelerate more rapidly with a heavy load, many folk expose themselves to
greater force under unloaded conditions! If one accelerates rapidly, the
effective weight or load imposed on the body DOES become significant! This is
always something we have to watch out for with beginners or those who believe
in using light weights.

< With this present myth of 90 degree angle, are you then suggesting that it
is appropriate for a beginner to do a deep knee bend? >

*** Do the persons suffer from any pre-existing knee problems or weakness? Do
they ever squat in daily life to put on shoes or play with youngsters? Do
they ever run, jump or kick without experiencing knee pain or disability? Is
there any good medical reason which definitely indicates that slow,
controlled full squats without major bouncing are dangerous for them? Do
they always want to have a limited range of functional knee flexion for the
rest of her life? Do they believe that the body was created or evolved NOT to
be used in a controlled fashion (and sometimes for emergencies) over the full
range of its capabilities? If the answer to all those questions is yes,
then let them continue to treat themselves as if they are ready for the
grave!

Also entirely relevant to the 90 degree story is the fact that more research
is emerging which shows that this limited range squatting can actually place
GREATER stress on the various structures of the knee joint than full range
movement.

My old Bulgarian weightlifting coach used to try to convince me that I should
even used a controlled bounce at the bottom of all of my squats in the clean
and snatch to ensure that I did not damage my knees!! He and many of his
colleagues did this for years with loads of as much as 240kg and after
several decades of lifting they still had no obvious knee dysfunction.

I have not come across any research which supports his advice, but it would
appear that he was recommending that one must involve the elastic structures
of the joints to augment the 'pure' muscle contraction characteristic of slow
controlled squats. Why rely just on muscles, when you can use stored elastic
potential energy as well and spare the poor old muscle, seemed to be his
view? I await information from others in this regard.

POSITION OF THE TORSO

Other contributors stressed the importance of squatting with the trunk
vertical, which is another one of those horrible myths about squatting. To
analyze this advice, let us return to the training chair that started all
this discussion.

Sit erect with knees in front of you (or a bit to the side), shoulder width
or so apart, hands folded across the chest, according to the advice we have
just read. Without leaning forwards or shifting the feet further back and
flexing the knees more, try to stand up without leaning forwards or bouncing!

You will find that this is impossible. To stand up, you either have to spread
your legs very wide apart, like the Sumo squat position of the powerlifter,
or move the feet backwards and lean forward. For most 'average' folk and
serious lifters, the latter position quite naturally teaches you your
individual degree of forward trunk lean for squatting and deadlifting. You
HAVE to lean forward to squat or deadlift (now don't quote some of those
weird 19th century lifts with the load behind the ankles to prove this
wrong!); that is determined by the biomechanics of the movement!

And never forget to hold the breath, even without a load, for this is what
nature decreed should happen to stabilize the trunk and protect the lower
spine! Your blood pressure will rise in proportion to the size of the load
and the amount of effort that you are willing to put into the action. If you
have cardiocirculatory problems, and you insist on squatting with weights,
then keep your mouth open and gradually breathe out to prevent intrathoracic
and intra-abdominal pressure from increasing too much - and avoid using
maximal loads!

< Regarding to POSITION OF THE TORSO during squatting: I believe many people
get confused by the advice to keep one's back "straight." Dr. Siff is right,
in my experience -- you can't keep your torso perpendicular to the floor
without some sort of odd foot position. But you MUST keep an arch in your
back. The technique I've always used is to keep the arch in the lower back
and neck buy sort of "pushing out" the chest and abdomen and looking slightly
upwards.

The belief that the spine must be straight during squats and deadlifts is
another one of those confusing snippets of ill-explained training lore. >

STRAIGHT BACK?

The 'advisers' probably mean that the spine should not be flexed forwards or
extended backwards, in some sort of hypothetical straight line. When
challenged on this point, some of them state that this is their simplified
way of stating that the spine should be kept in its neutral position,
whatever that means in the context of a dynamic lift involving a line of
action which changes all the time relative to the direction of the
gravitational pull.

PATTERNS AND RHYTHMS

Some authors (e.g. Cailliett 'Low Back Pain & Disability') refer
simplistically to a lumbar-pelvic rhythm that must be followed to ensure safe
lifting (or squatting), but we have to look at the whole body as a linked
system to appreciate that the actions of squatting and lifting involve many
more actions than those of the pelvis and lumbar spine alone. However, these
authors are correct in identifying that there is a characteristic rhythm or
timed pattern of anatomical (kinesiological) action for the optimal and safe
execution of every exercise.

In the case of the squat, there is a definite rhythm of how the different
joints (ankle, knee, hip, spine) become involved in producing an efficient
and safe movement. This rhythm or timed pattern is really like an exquisitely
orchestrated symphony conducted under automatic and voluntary control of our
brain and nervous system. Every instructor or coach has to conduct a client's
orchestra to produce individualized nervous programs in the brain so that the
muscles will obey the commands to execute an exemplary squat.

POSTURE AND NEUTRALITY

One must maintain a definite lumbar curve during the squat, but this is where
some authorities differ. Some consider that this constitutes lumbar
hypertension and can damage the spine, so they talk about neutral posture,
even though neutrality is defined to apply under static standing upright.

As soon as you lie down or tilt the spine relative to gravity, then we can
attempt to maintain the three natural mobile curvatures of the spine
(cervical, thoracic and lumbar), but this necessitates increasing muscle
tension and changes in other joint angles to approach this standard of
'neutrality'. So, the appearance of neutrality is quite different under
different actions. Even though the spine looks like it is structurally in the
same relative shape, functionally the muscles, ligaments and other tissues
are in radically different states of tension and operation. In other words,
the concept of neutrality (like all the ideas about pelvic tilt) is not at
all as clear-cut as out medical and physiotherapeutic colleagues would have
us believe.
 
part 3

APPROPRIATE LUMBAR POSITIONING

To resolve the issue of lumbar 'hyperextension' during squatting or lifting,
we must analyze what stabilizes the spine under different conditions. The
muscles act as dynamic or static active stabilizers (since they can
contract), while the ligaments act as passive stabilizers (they cannot
contract). In maintaining the three natural spinal curvatures, it is pleasing
to know that both the muscles and the ligaments (and other tissues such as
the fascia, as well as the pressurised trunk) all cooperate to stabilize the
spine.

However, we cannot say that the loading is distributed equally between
muscles (e.g. erector spinae) and ligaments. This ratio is determined by
one's way of squatting. So, if one tightens the erector muscles as much as
possible, this may cause some of the ligaments to slacken, thereby placing a
greater load on the muscles. If one avoids tensing the erector muscles too
much or allows the lumbar spine to arch forwards, then the ligaments may bear
much greater stress and the muscles tend to decrease their strength output.

DYNAMIC STABILIZATION

It happens that there is an optimal balance between these two undesirable
extremes which allows the contribution by muscles and ligaments to
dynamically adjust to different phases of the squat from the starting to the
end position. The trainee or lifter learns this optimal dynamic balance by
tons of experience, some of which is by the bitter way of making painful or
damaging errors.

There is not one precise static position of the spine or hips, though there
is a typical ratio at each set of joint angle (knees, hips, spine, neck
etc.). The ratios change over the range of movement and one learns to develop
great proprioceptive skills to enable you to adjust rapidly and
automatically.

So, we can now appreciate how inadequate it is in the overall picture to
learn by squatting onto a seat or in a part range movement from which we are
told never to deviate, because one must use a specific single type of pelvic
tilt, lumbar angle of concavity, knee angle and so forth.

OBVIOUS ADVICE

We can, of course, make cautionary statements about avoiding actions which
have been seen to have caused serious injuries during squats and all
exercises, for that matter - such as rounding the lower back and twisting
simultaneously, bouncing vigorously in an uncontrolled fashion on totally
relaxed, using a weight which is too heavy to maintain appropriate technique,
bouncing the buttocks off a seat while using a significant load or
accelerating rapidly and squatting when one is fatigued, sore or injured.
Such advice is wise and advisable. But first and foremost are the rules that
perfection of technique and intuitive sensitivity to any changes will go a
long way to preventing injury and ensuring progress.

-------------------------------

Met dank aan Mel C Siff
 
Op vraag van Matthieu die vindt dat er geen leuke posts meer zijn... een van de aller aller eerste posts van dit forum !!!
 
Hmm, als ik thuis ben even doorlezen ;) Ben benieuwd wat voor dingen er in het artikel staan die in de afgelopen 10 jaar juist weer zijn ontkracht.
 
Goed bezig Spike.. Ik ga t van de week ook eens lezen.,
 
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