Analysis of Human Movement 473from personal experience of incorrect and correct
execution of a given movement before one can make
an appraisal of “excessive.” In other cases, “normal”
is more intuitively obvious or is set by the aesthetic
of a given school of dance.
Some examples of common problems to look for
are provided in table 8.2. These errors can come
from many sources including inadequate stabiliza-
tion of prime movers, inadequate use of synergists to
neutralize undesired secondary actions of muscles,
unbalanced co-contraction of antagonist muscles,
inadequate muscle contraction to counter external
forces, and inappropriate weight placement (or com-
binations of these). In some cases the problems may
be linked to inadequate or imbalanced strength or
flexibility in select muscles, while in other cases the
problems may relate more to neural control factors
and suboptimum coordination of muscles to pro-
duce desired movements. When movement analysis
is being performed, key alignment and technique
errors should be noted; and if the analyst has suf-
ficient knowledge, brief suggestions for improving
these problems can be given. Sample strength exer-
cises, stretches, mechanics, and cues that may help
improve these problems are provided in table 8.2.
However, if recommendations are to be given in
an effort to correct these technique problems, notonly is a knowledge of “normal” required
but also a skillful analysis is necessary so
that appropriate corrections can be gen-
erated that will enhance performance
and not just create new problems. One
important aspect of this skill is the abil-
ity to distinguish a causal relationship
between errors and decide if something
is a problem in itself or is an effect result-
ing from another more fundamental
problem. Another important consider-
ation is the ability to prioritize problems
and decide which areas to address first.
One key factor that influences this pri-
oritization is how much improvement
would be expected from the correction
of a problem.
Although there are many approaches
that can be taken, one approach com-
monly used by the author is to begin with
more central or proximal corrections,
as these corrections often positively
impact performance, as well as influ-
ence more distal problems. For example,
when addressing a dancer performing aFIGURE 8.7 Sample dance movement demanding high
levels of upper extremity strength.
Photo courtesy of Patrick Van Osta. CSULB dancer Delyer Anderson.FIGURE 8.6 Sample dance movement demanding high levels of strength of
the knee extensors.
Photo courtesy of Patrick Van Osta. CSULB dancers Shana Menaker and Dwayne Worthington.