Mel Siff Writes:
>
>*** The continued implication is that many people (yes, some articles even
>claim that the vast majority of people, including top athletes, have
>defectively functioning TVA or MTF) do not display an involuntary ability to
>activate or timeously use these muscles.
>
>As I asked in an earlier letter, does this mean that even the extremely
>demanding conditions of competitive weightlifting and powerlifting (as well,
>as track and field, wrestling and many other very forceful sports) simply are
>unable to produce involuntary, adequately efficient action of TVA and MTF?
>Are we to assume that the execution of a heavy squat, clean, snatch, pole
>vault, wrestling throw, overhead jerk and similar movements will not activate
>TVA and MTF as effectively as the current rather static and low-force
>conditions recommended by various therapists?  If so, I would be most
>interested to see the scientific evidence that shows this.  For example, even
>the forceful expulsion or forceful holding of breath has been shown by
>Basmajian to strongly activate TVA ("Muscles Alive"), and those actions are
>common in all of the activities that I have mentioned.
>
>Further to this, is there any evidence to show that the progressive, graded
>use of weightlifting and powerlifting derived exercises does not produce
>involuntarily the same or greater degree of dynamic TVA and MTF efficiency as
>the current regimes of voluntary TVA and MTF exercises combined with more
>therapeutic exercise activities?  Note, before someone responds by decrying
>the use of competitive lifting exercises, I am NOT stating that one has to
>learn or use every competitive lift, but to progressively and sensibly use a
>variety of the many hundreds of movement variations that may be derived from
>the basic weightlifting and powerlifting movements.
>
>However, I am suggesting that future findings may well show that anyone who
>regularly trains with weightlifting and powerlifting derived variations will
>automatically acquire the ability to efficiently use TVA and MTF (even though
>static clinical tests may suggest some 'deficiencies' under non-sporting
>conditions).  I eagerly await reading more research in this direction.
>
>Dr Mel C Siff
>Denver, USA
>http://groups.yahoo.com/group/Supertraining/

John Replies

Mel, the more I read your posts the less convinced I am that you have
read the research on this matter by Hodges, Jull, Hides et al.  I only
say this because you appear to have read sources that are telling you
things that appear to be way off base with this research.

Dysfunctional TVA is not defined AT ALL by an inability to produce a
contraction of the muscle.

Dysfunctional TVA is defined by it's inappropriate recruitment in terms
of TIMING in that, instead of activating in advance of other muscles (eg
shoulder muscles in a throwing motion), it activates late, thereby
proving unable to adequately stabilise the lumbar spine.

Why should we think that weight-lifters are able to 'correct' this
timing just by merit of the fact that they lift heavy weights in a
particular way? Think of the correct use of TVA as a 'skill' that people
lose rather than just the ability to contract it at all. The research
indicates that many people who use skilled, effortful methods in their
sports still have a deficiency in the core stabilisers.

I use the analogy with my patients of learning to juggle - we are going
to teach them a 'skill'. Implying that weight lifters can 'juggle' just
because they have big muscles and can throw balls a long way would be
equally bizarre.

In fact personal comments from the researchers suggest that those
individuals that tried to rehab TVA by using explosive, high resistance
movements actually resulted in WORSE timing of TVA and more pain and
dysfunction.

Why would you want to rehab a muscle that works most effectively at very
low loads (as low as 5% MVC of MTF has been indicated as being adequate
to stabilise the lumbar spine) by using high resistance, explosive
techniques?

You mentioned in your first post about 'more and more scientific
research' that is emerging to disprove the work of TVA researchers.
Particularly the work of Dr Stuart McGill. I would be really grateful
for the references.

Similarly I would be interested in any references that suggest core
stability work is best carried out in 'isolation' or in the absence of
'functional activity' - I have still not come across any.



--
John Spencer