Ironically, this is an important tenet in Dynamic Stabilisation work Mel.
Anatomically, certain muscles (the 'deep stabilisers' such as Multifidus)
are not well placed to produce movement (short levers, closer to the centre
of rotation of the spinal segments). Transversus Abdominus, for instance,
doesn't produce movements of significance across joints. But these muscles
are able to increase 'stiffness' of intervertebral segments.
Certainly EMG movements show that activity in these muscles occur in the
'feedforward' mechanism you refer to, firing about 30ms before any activity
is produced in the shoulder muscles when a subject is asked to lift their
arm.
I guess the original statement was an attempt to counter the temptation of
anatomical reductionism where muscles were studied in isolation
Did you know that the first person to hypothesise that the neck had muscles
dedicated for movement and muscles dedicated to stabilise was Leornardo Da
Vinci? (He suggested that the more central muscles stabilised the bones of
the neck, one on another, and the more lateral muscles acted as 'guy ropes'
supporting the vertebrae as they would the mast of a ship, able to work in
concert to bend the mast in any direction)
John Spencer
----- Original Message -----
From: <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, August 16, 2002 5:51 AM
Subject: Movements not Muscles?
> Several decades ago, possibly in a text written by Guyton or Bernstein, I
> learned of this well-known physiological aphorism: "The body knows of
> movement, not muscles" and I periodically have reincanted this in various
> articles or seminars, but I have always entertained some reservations
about
> its validity in general.
>
> Why should I have doubted its correctness? After all, it was emphasized
by
> world authorities such as the late great Russian scientist, Bernstein!
Now I
> no longer am willing to accept anything at face value, possibly because I
> have become increasingly skeptical about many of the "facts" that are
taught
> in sports science and therapy.
>
> There are a few reasons why we need to re-examine this saying:
>
> 1. Bodybuilders in their posing routines are able to "flex" various
muscle
> groups without moving any joint or limbs. They can "bounce" their pecs,
> tense their quads and calves, select parts of the abs and tense them
> alternately without any trunk action. In short, by focusing specifically
on
> certain muscles they eventually gain a large measure of control over
certain
> muscle groups without the need for any limb motion.
>
> 2. EMGs that have been taken of certain muscles have shown that the
muscles
> can tense in anticipation of any movement that is about to take place (as
in
> jumps from a height). In other words, the "virtual reality",
> feedforwarding", "imagineering" or anticipation of movements or muscle
> activation can stimulate muscle action before any movement takes place.
>
> 3. Biofeedback training, especially using EMG as an intervention, can
teach
> a person how to control specific muscle action without any movement taking
> place.
>
> That is why in more recent times I have preferred to state that "the body
> usually knows more about movement than muscles, but there are exceptions
to
> this general rule that may be important in motor control." So, before we
> reflexively repeat that old saying, let us think very carefully about the
> exact situation and context in which we believe it to apply, for we may be
> neglecting some important exceptions to the "general rule."
>
> Dr Mel C Siff
> Denver, USA
> http://groups.yahoo.com/group/Supertraining/
>
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