Editors note :

The importance of the optimal functioning of
the central nervous system in athletic training is often
either overlooked entirely or is relegated secondary
status to the development of strength.
And frequently even the type of strength
training recommended is inappropriate. For example,
in Olympic style weightlifting the spatial and temporal
characteristics of the classical lifts (the snatch and
clean and jerk) are such that explosive strength is a
far more important functional indicator of success than
absolute (or maximal) strength.
Yet how often are pulls and squats with
weights that bear little relation to what a lifter can
actually snatch or clean and jerk recommended as
being beneficial ? Also, inordinate amounts of energy
are sometimes spent deadlifting (in various forms and
fashions).

What follows is an excerpt from the writings of a
most distinguished sports scientist, the late Professor
Mel Siff. The topic is "Neural Changes with Training"
and the interested reader may find some of the results
surprising.

Neural Changes with Training

The fact that neuromuscular stimulation is
fundamental to all athletic training is emphasized
further by recent findings that sensory experience
results in enlargement and other changes in the
cerebral cortex. Earlier hypotheses that the central
nervous system cannot change after adulthood have
now been proved to be incorrect. It was generally
recognized that the young brain has a great capacity
to adapt to changes such as injury or disease, but that
neural tissue in the mature animal is unable to display
this plasticity. Rosenzweig (1984) has concluded that
the capacity for plastic neural changes is present not
only early in life, but throughout most, if not all, of the
human lifespan. These changes become particularly
evident if one is exposed to a sufficiently rich
environment providing novel, complex, and cognitively
challenging stimulation, a finding which stresses the
importance of not limiting one's training to simple,
largely unchallenging repetitive patterns of training
with exactly the same weights or machines. This is
one of the main reasons why this text emphasizes the
importance of planned variation utilizing numerous
different means, methods and exercises which draw
on integrative whole body disciplines.
The work of Rosenzweig, Diamond and colleagues
at Berkeley has not only revealed that neural changes
occur in adulthood, but that these changes can occur
easily and rapidly. Greenough at the University of
Illinois found that these alterations in the central
nervous system not only increase mass, but other
structural changes such as the formation of new cell
synapses and dendrites.

These findings have profound implications for
athletic training, particularly the following :

1) Athletic training not only causes physiological and
functional changes in the motor and cardiovascular
systems, but also in the central nervous system.

2) Strength training on machines that restrict the
movements of joints involved in producing a specific
sporting action can modify the circuitry and
programming of the brain and thereby reduce the
functional capability of many of the muscles used to
execute that movement.

3) The rapidity of changes produced in the brain by
repeated stimuli means that even short periods of
inappropriate patterns of strength training can be
detrimental to sporting performance. The
importance of understanding the complexities of
prescribing concurrent and sequential methods of
training in the short and the long term then becomes
obvious. This necessitates a thorough knowledge of
phenomena such as the delayed training effect, the
long term delayed training effect, and the conjugate
sequence method.

4) Over-reliance on ergogenic devices such as lifting
belts, hand grips, bandages for the joints, special shoe
inserts, wedges under the heels for squatting and
elasticized training suits can modify the
neuromuscular system to such an extent that efficient
of safe training without them becomes difficult.

5) The avoidance of certain exercises (such as those
often condemned by popular fitness training
organizations) and the use of compensatory muscle
action can alter the dynamic balance between
interactive muscle groups and alter neural
programmes so as to reduce the capability of handling
certain functional movements efficiently and safely in
sport and daily activities.

6) If the likelihood of total rehabilitation of an injury is
remote, than the teaching of compensatory muscular
action can be valuable in maintaining a high level of
functional capability.
7) The existence of individual style reveals that each
person will program the central nervous system in
subtly different ways, so that attempts to impose
stereotyped, highly general patterns of movement may
prevent an athlete from ever reaching his true
potential.
8) Subtle differences apparently as insignificant as a
change in grip, stance or head position in regular
training can cause significant neural changes which
control the way in which an athlete executes a given
skill.