GENERAL STUDIES OF THE SIT TO STAND MOVEMENT
published in STATNews, September 2011)
By Tim Cacciatore
The reason for studying the ATís effect on standing up
(i.e. sit-to-stand) is, of course, that chair work is
fundamental to the AT.
Understanding the underlying physics and neural
control will hopefully yield general insight into AT
principles, such as mechanical advantage and the
While such insight could probably be gained by
studying other AT procedures, the extensive research already
performed on sit-to-stand will undoubtedly be advantageous
in helping reveal the AT's effects on coordination.
To date, several hundred research papers have been published
on sit-to-stand. The first of these was by Frank Pierce
Jones, which is remarkable given both his background and the
technology available in the 1960s.
It wasnít until thirty years later (about 1990) that
the sit-to-stand movement was actively researched and some
of its basic underlying biomechanics were understood.
Sit-to-stand, like all whole-body movements, is brought
about by the precise coordination of many muscles.
Surprisingly, little is known about how the nervous
system coordinates such extensive activity during whole-body
understanding the role of an individual muscle is daunting
because it can have complex, whole-body effects.
Thankfully, however, the coordination of whole-body
movements can be understood in terms of three simple but
fundamental mechanical problems, or constraints, that our
nervous systems must solve.
These constraints are: 1) keeping the bodyís centre
of mass between foot and seat contact (i.e. to maintain
balance); 2) providing antigravity support (to prevent
skeletal collapse); and 3) generating the forces necessary
The basic phases of the sit-to-stand movement can easily be
understood in terms of these three mechanical constraints.
One begins to stand up by inclining the upper body
forward, which moves body mass toward the feet in order to
maintain balance after lift-off (constraint 1).
If you think you donít need to lean forward to stand
up, move your feet forward by about 30 cm and try again.
Prior to leaving the chair, hip and knee extensor
muscles are activated to provide antigravity support for
these joints (constraint 2).
This is also commonly referred to as "weight shift".
Finally, after leaving the chair, the leg and trunk
joints are straightened to achieve upright stance
While this description may seem overly mechanical and
irrelevant from an AT perspective, these basic mechanical
constraints must be satisfied, even when standing up with
Moreover, our research described below suggests that the AT
enables one to satisfy these constraints in a different way.
In addition to characterising the basic movement phases,
previous non-AT studies of sit-to-stand have quantified the
coordination of hip, knee and ankle movements, the effect of
different chair height and foot positions, as well as
coordination differences that occur from ageing and disease.
A number of other studies have focused on the
specifics of balance -how far forward and how fast the mass
must travel in order to stand up.
While many studies have measured overall forces
(torques) occurring at hip, knee and ankle joints as well as
the electrical firing patterns of many muscles, neither the
stiffnesses in joints nor the forces exerted by individual
muscles have been measured during this action, as this is
In general, there has been an overabundance of
studies examining the strength required, because some
researchers think weak quadriceps muscles underlie
difficulty standing up in old age.
This notion is highly contentious, however. Finally,
several groups have characterised spinal bending during
sit-to-stand (i.e. pulling the head back, and hollowing the
the cause and relevance of these spinal movements is not yet
PREVIOUS STUDIES ON THE EFFECTS OF AT ON SIT-TO-STAND
Jones et al  and Stevens  directly examined the
effects of the AT on sit-to-stand coordination.
Because these papers were published long ago and are
still referred to by the AT, it is pertinent for us to
understand what these findings mean today, as both the
knowledge base and publication standards have changed
While Jones performed several studies on sit-to-stand, only
one of these focused on the effects of the AT .
This study compared coordination with AT hands on
guidance prior to, or throughout the movement to unguided
He also tested subjects before and after they had a
series of lessons.
His main measures of coordination were movement
trajectories, obtained from film.
He quantified angles of the head and neck, chest, the
lowest position of the head, as well as its maximal
horizontal velocity and vertical acceleration.
He found that the AT affected many of these,
including the head/neck and chest angles as well as reducing
maximal head velocity and acceleration.
In general, the largest AT effect was with full
guidance, compared to adjustments only or lessons alone.
However, by today's standards, interpreting the use
of guidance during the movement is problematic because it is
difficult to determine the confounding mechanical effect of
he later obtained a plate for measuring forces under the
feet, only data from a single trial from each condition were
Stevens and colleagues published a paper on sit-to-stand in
1989 . The
primary focus of this study was to examine how foot
placement (habitual vs. standardised) affects the movement.
In addition, they examined the effect of an AT
teacherís hands on guidance on coordination.
While changes in foot forces, muscle activity and
movement were noted, the result is considered anecdotal
because it was performed on a single person.
In addition, because Stevens only assessed the AT's
effects through hands on guidance, it is difficult to
interpret the data.
From todayís perspective, these studies provide evidence
that the AT does change sit-to-stand, including spinal
coordination, overall movement trajectory, as well as
maximal acceleration and velocity.
Unfortunately, little else can be concluded about the
ATís effect on the mechanics or neural control of this
LACK OF AND IMPORTANCE OF THEORY IN THE AT
While the work of Jones forms an extensive body of carefully
conducted, pioneering research, it fails to provide a
plausible modern scientific basis for the AT.
This failure does not result from the quality of the
original work, but from the lack of subsequent research over
the last 40 years.
Jones did formulate a theoretical framework to explain his
data that was appropriate for the time.
This hypothesis was that altered head-neck reflex
responses caused the coordination changes he observed.
Jones later referred to this proposed reflexive
change as a change in "postural set", meaning a cognitive
state that affects automatic behaviour.
While we understand his motivation from our
subjective AT experience, this cannot be concluded from the
neither head-neck reflexes nor postural set was measured,
thus there is no empirical support that such changes
Today, this extent of speculation in a primary
research publication is not permissible.
Second, the idea that a particular head-neck
relationship unleashes reflexive automatic coordination is
not tenable. Magnus' head neck reflexes are known to
disappear early in development, and generally speaking motor
coordination is known to be much more complex.
While Jones' experimental data still stand, the importance
of his emphasis on head and spinal coordination has not been
Because of this, his research has had little impact
on the scientific literature, outside research on the AT.
Jones was ahead of his time: he studied how the AT affected
sit-to-stand coordination before sit-to-stand coordination
In all of science there are only two things that make a
topic important: either it has a clear theoretical basis or
there is very carefully controlled, compelling experimental
evidence that indicates its importance.
An example of the former is the current search for
the Higgs particle -enormous sums are being spent on the
LHC at CERN because of its theoretical importance.
An example of the latter is the ATEAM trial, where a
carefully controlled RCT found that the AT helps back pain.
Even in the latter case, however, there is resistance
to the experimental ATEAM result, because no clear
theoretical basis exists for why the AT reduces pain.
This reflects the tremendous emphasis in science
placed on understanding why things happen -not just what
Today, we continue to face the same difficulty as Jones
because the principles and practice of the AT still lack a
clear theoretical basis.
Because it is not obvious why the measures that Jones
quantified, such as the "head/neck angle" or "chest angle",
might fundamentally affect the sit-to-stand movement, it is
difficult to argue convincingly for their relevance. This is
also true of many phenomena in the AT, such as "pulling the
"pulling the knees in" , "jumping out of the chair" and
As opposed to being fundamental, all these observations are
considered phenomenological, which means that they canít be
derived from theory.
Without additional theoretic underpinnings such
measures will attract little scientific attention.
It is difficult to formulate a plausible theory for the AT
because it likely lies at the border between neuroscience
and mechanics, and itís not clear exactly how much of each
contributes to a given AT principle, practice or
one hand, neuroscience (especially motor control) is a young
field with much to be learned and relatively few established
the neuroscience principles necessary for understanding the
AT may not be known yet.
On the other hand, mechanics is a mature field where
the theories (mainly based on Newtonís laws) are
established, but deceptively complex.
Thus while there could be a mechanical basis for a
phenomenon in the AT, for example lifting the heels off the
ground as one moves to sit down, its mechanical basis could
be difficult to formulate.
Without a theory of the AT, it will be necessary to rely
more heavily on experimental evidence for its concrete
benefits to establish a wider recognition of the value of
While performing illuminating experiments on AT benefits is
not always straightforward, the challenges are soluble, and
such evidence will likely continue to mount.
It will be the establishment of a plausible theory
for the AT, its principles and methods that will be the
major challenge to scientific research ahead.
Part of the difficulty we face is that we often confuse our
experiential understanding for scientific understanding.
We disguise our scientific ignorance with vague but
unsupported explanations of why the AT works.
For instance, Jonesí work is often mentioned in
conjunction with two of these unsupported theoretic notions:
that either postural reflexes or the startle pattern relate
to the ATís mechanism.
Clearly the AT changes some type of automatic
However, strictly speaking, a reflex is a specific
type of stereotyped automatic reaction.
While the AT may indeed affect such reflexes, to our
knowledge no study has examined the ATís effect on them.
In contrast, Jones did measure the startle pattern
and noted that it resembled poor coordination .
However, as with reflexes, the effect of the AT on
the startle pattern has not been quantified, and thus there
is no experimental support that the startle pattern
underlies poor Use.
While the lack of a plausible scientific theory has not
prevented the AT from being taught or passed on,
exaggerating our understanding of its underlying mechanism
has downsides, whether we do so knowingly or not. It
tarnishes our credibility and hinders our willingness to
accept a more valid and explanatory theoretical framework as
Admitting we don't really know why the AT works doesn't
undermine our competence to practice and teach this profound
experiential body of knowledge.
RECENT STUDY ON AT SIT-TO-STAND COORDINATION
"Prolonged weight-shift and altered spinal coordination
during sit-to-stand in practitioners of the Alexander
by Tim Cacciatore, Victor Gurfinkel, Fay Horak and Brian Day
While the purpose of this study was to better understand how
the AT affects sit-to-stand, the results begin to suggest a
theoretical basis for some general AT principles, which we
describe at the end.
The experiment compared sit-to-stand coordination between 15
AT teachers and 14 matched control subjects.
Subjects were asked to stand up "as smoothly as
possible without using momentum" five times while their
movement and foot force were measured.
To assess the effects of the AT we examined several basic
measures of coordination.
First we quantified the duration of various phases of
sit-to-stand -the time to: a) lean the trunk forwards, b)
shift weight to the feet, c) transfer momentum from the
upper to lower body, d) straighten the legs and rise to
While the overall time to complete the movement was similar
between groups, two of the phase durations were markedly
First, AT teachers took twice as long to shift their weight
onto the feet (roughly 20% of the movement vs. 10% for
Second, teachers spent less time transferring momentum,
which suggests they used less forward upper body momentum to
stand up. In addition
to taking longer, teachersí weight shift was smoother.
While control subjects abruptly took weight off their
feet before increasing it, AT teachers simply increased the
weight smoothly (this agrees with the preliminary
observations from Jones and Stevens).
We think control subjects use this unloading to
increase their forward momentum.
Because AT teachers' weight shift was prolonged, it lasted
from the beginning of trunk inclination up until lifting off
the chair. In
contrast, controls shifted all their weight at a specific
trunk angle, just before lift-off.
This means teachers are able to solve the balance
problem (i.e. shift their mass forwards toward their feet)
at the same time they generate antigravity support for the
contrast, control subjects stand up as two separate
sequential actions -leaning forward, and then rapidly
We think this ability to solve these two basic
mechanical problems simultaneously is fundamental to chair
Interestingly, data from a previous study suggests young
children may also have this ability.
We think that controls had difficulty standing up in a
single continuous action, because simultaneously bringing
their mass forward and shifting weight requires that hip and
knee extensor muscles lengthen while generating large forces
(i.e. contract eccentrically).
This means that an even stronger force must pull on
the ends of these muscles, so that they lengthen and keep
the body mass moving forward.
One potential source of energy for this force is the trunk.
It is interesting then that the lower spinal bending
we observed in AT teachers (in neck, thoracic and lumbar
regions; also consistent with Jones' findings in the neck)
theoretically helps to transfer mechanical energy from the
trunk to the limbs.
This would help lengthen knee and hip extensors and
could enable teachers to stand up in one continuous action
(i.e. simultaneously bring the body mass forward and shift
Our recent finding that the AT changes muscle tone  may
also be relevant to teachers' ability to stand up.
The lower stiffness in teachers' hip muscles would
make these easier to stretch during sit-to-stand.
The greater responsiveness of neck and back muscles
would help transfer mechanical energy across the spine.
However, for sit-to-stand, the increased
responsiveness would have to act to oppose length changes,
rather than the yield, as occurred during twisting.
These results naturally suggest a hypothesis regarding
Alexanderís concepts of mechanical advantage and
Specifically, this hypothesis consists of several
parts: 1) the essential feature of mechanical advantage is
that it requires lengthening contractions in the limbs while
opposing gravity; 2) this requires an efficient transfer of
energy across the trunk; 3) the HNB relationship facilitates
this transfer of energy; 4) responsive tone acts to 'allow'
lengthening in leg extensors by yielding; 5) responsive tone
acts to maintain the HNB relationship by opposing length
changes in neck and trunk muscles.
It is notable that the main procedures of mechanical
advantage (standing up and sitting down in a chair, monkey,
lunge and squats) all theoretically require lengthening
contractions in leg muscles while opposing gravity.
Thus, this may explain why these specific procedures
are so beneficial for teaching the HNB relationship.
While this hypothesis plausibly explains our findings for
sit-to-stand as well as other aspects of AT behaviour, it
doesn't shed light on the complexity of the underlying
muscular coordination, and it is preliminary.
There is much more to the AT that it doesn't address,
of course, such as what cognitive and attentional processes
are involved, AT principles such as inhibition, or how these
mental phenomena relate to motor coordination.
However, it is a start.
Many more studies are needed to understand it in
detail, test it directly and determine what aspects of it
Jones FP, Gray FE, Hanson JA, Oconnell DN. An
experimental study of the effect of head balance on patterns
of posture and movement in man. Journal of Psychology.
Stevens CH, Bojsen-Moller F, Soames RW. Influence of
initial posture on the sit-to-stand movemnt. Eur J Appl
Jones FP, Hanson JA. Postural set and overt movement:
a force platform analysis. Perceptual and Motor Skills.
Jones FP, Hanson JA, Gray FE. Startle as a Paradigm
of Malposture. Perceptual and motor skills. 1964;19:21-2.
Cacciatore TW, Gurfinkel VS, Horak FB, Day BL.
Prolonged weight-shift and altered spinal coordination
during sit-to-stand in practitioners of the Alexander
Technique. Gait & posture. 2011.
Cacciatore TW, Gurfinkel VS, Horak FB, Cordo PJ, Ames
KE. Increased dynamic regulation of postural tone through
Alexander Technique training. Hum Mov Sci. 2011;30(1):74-89.
Tim Cacciatore 2011