The rationale for a motor control programme for
the treatment of spinal muscle dysfunction
C. A. RICHARDSON, J.A. HIDES
OVERVIEW
Therapeutic exercise for low back pain has traditionally focused on programmes for enhancing
cardiovascular fitness, as well as trunk muscle strength and endurance.
More
recently,
exercises
which
address
changing
motor
control
strategies in back pain patients, have been recommended. This course
describes the rationale for the proprioceptive antigravity training model,
for the prevention and treatment of low back pain
KEY WORDS
Low back pain; Motor control dysfunction rehabilitation; Weight-bearing exercise; Antigravity muscle function; Unloading
skeleton
1.
individual joints of the lumbar spine but also on
INTRODUCTION
their function as part of a larger antigravity
Therapeutic exercise for low back pain has
system which ensures joint protection while
traditionally
transferring load safely and efficiently through
focused
on
programmes
for
enhancing cardiovascular fitness as well as
the
trunk muscle strength and endurance.
therapeutic
recently,
exercises
which
address
More
changing
lumbopelvic
exercise
region.
An
model,
expanded
proprioceptive
antigravity training, incorporates the additional
motor control strategies in back pain patients
load
have
health
muscles. In essence, such training consists of
professionals involved in treating low back pain.
the initial activation of the deep muscle system
One
segmental
to 'stiffen' the joints in preparation for weight
stabilization model, was described in a text by
bearing, followed by the integration of the deep,
Richardson et al (1999) and was based on
local muscle system into full weight bearing
considerable research which focused on the
function
function and dysfunction of the deep muscles of
exercise, with the emphasis on slowly increasing
the lumbopelvic region. Further research has
proprioceptive load cues.
been
motor
recommended
control
by
method,
many
a
transfer
function
through
of
the
progressive
antigravity
antigravity
been completed in many different associated
areas and the result is an extension of this
While
motor control model. The updated segmental
exercise model is closely associated with the
stabilization model focuses not only on the
management of musculoskeletal conditions of all
function
limb joints, this chapter will focus on providing
of
the
deep
muscles
to
support
the
updated
segmental
stabilization
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
the rationale for the model in relationship to
programme
remains
with
the
segmental
management of low back and pelvic pain.
stabilization (deep muscle support) concept, but
it is its role in weight bearing, rather than
2.
2.1
THE RATIONALE FOR THE
PROPRIOCEPTIVE ANTIGRAVITY
TRAINING MODEL FOR THE PREVENTION
OF LOW BACK PAIN
movement, which is highlighted.
2.2
The segmental stabilization model of
exercise
A historical perspective
For the development of this part of the model, it
A new type of stabilization exercise for the
is necessary to first differentiate the synergists
management of low back pain was developed by
into local and global muscle categories, where
physiotherapists at the University of Queensland
'local' refers to smaller, deeper muscles which
in the early 1990's. It placed a new focus on
are closely related to the stability of a joint but
exercise to relieve pain through activation of the
deep
muscles
transversus
abdominis
do not produce joint torque and 'global' refers to
and
the large superficial muscles which generate
multifidus in back pain patients (Richardson &
joint torque and are responsible for movement.
Jull 1995). This approach was different to other
stabilisation exercise programmes designed for
low back pain as it had a focus on segmental (or
Muscle dysfunction of the local system of
the lumbopelvic region
individual joint) stabilization. The emphasis was
The research which led to an emphasis on the
on changing the neural control of the muscles
deep
which were directly related to the stabilization
stabilization concept involved ne experimental
and protection of the joints of the lumbopelvic
models
region prior to focusing on functional patterns
dysfunction of the local muscles to be assessed
involving the whole body (Richardson et al
and quantified. For the deep lumbar muscles
1999).
this
local
muscles
which
was
and
allowed,
achieved
by
for
the
the
the
segmental
first
time
identification
of
dysfunction in the lumbar multifidus by Hides et
The segmental stabilization model of exercise
al in 1994 using real-time ultrasound, and
has been modified and extended. This has been
dysfunction
possible through involvement in space research,
transversus abdominis by Hodges & Richardson
which
in 1996 using a trunk perturbation model with
has
relationship
given
new
between
insights
synergistic
into
the
muscle
fine
function, gravity and joint loading. The model
wire
of
EMG
the
to
deep
abdominal
assess
the
muscle
recruitment
patterns of the deep muscles.
now includes muscle support for each joint in
the kinetic chain for the integrated function of
Multifidus had long been recognized as an
weight bearing through the spine, pelvis and
important
lower limbs. However, the essence of the
protection of the lumbar spine (Goel et al 1993,
2
muscle
in
the
stabilization
and
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
Quint et al 1998, Wilke et al 1995). Hides et al
were obtained. Only the multifidus at the lowest
(1996) demonstrated a segmental loss of cross-
lumbar level was statistically smaller in LBP
sectional area in the lumbar multifidus in acute
patients than in controls.
first episode low back pain and went on to
explain this loss of muscle cross-sectional area
In comparison to multifidus, there were few
as
biomechanical research studies which addressed
indicative
inhibition
of
(for
segmental
recent
muscle
review
see
reflex
Hides
&
the function of transversus abdominis. Initial
Richardson 2002) which did not resolve on
studies of Cresswell et al (1992) demonstrated
resumption of normal activity and relief of the
that the transversus abdominis remained active
low back pain.
during repetitive trunk flexion and extension,
while the global trunk muscles switched on and
These
findings
segmental
off depending on the direction of movement. A
stabilization model substantially as Hides and
further study investigated the response of the
colleagues went on to demonstrate, through
transversus abdominis to perturbations, and
clinical research, that patients who learned to
showed that the response of the transversus
reactivate
abdominis was of short latency (Cresswell et al
their
influenced
multifidus
the
through
specific
exercise techniques, with the aid of real-time
1994).
ultrasound feedback, not only corrected the loss
studied
of cross-sectional area (CSA) but 3 years later
abdominis to perturbation, this time induced by
had significantly fewer recurrences than the
movement of a limb in response to a stimulus.
control group who had medical management
The
alone (Hides et al 2001). Through this clinical
abdominis was activated in a feed-forward
research it was also discovered that the deep
manner (prior to the deltoid in upper limb
and
movements), and this response was unrelated
superficial
parts
of
multifidus
were
Hodges
the
results
Richardson
response
indicated
that
the
transversus
Richardson 1997). This reaction was in contrast
pain (Hides 1996). This was recently verified by
to that of the superficial muscles, which reacted
Moseley et al (2002) who used fine wire EMG to
to the direction of limb movement. This study
determine the function of the two separate parts
suggested that the transversus abdominis has a
of
separate
evidence
has
control
movement
transversus
which was the problem in patients with low back
Recent
of
the
also
to
muscle.
direction
of
(1996)
functionally different and it was the deep part
the
the
&
mechanism
(Hodges
and
that
&
its
demonstrated that problems in multifidus also
function was likely joint stabilization.
occur in chronic low back pain. The CSA of the
studies
multifidus is selectively decreased in chronic LBP
mechanism of this muscle in relation to the
patients
controls
stabilization of the spine. Hodges et al (1997)
(Danneels et al 2000). Cross-sectional areas of
also demonstrated that the response of the
the multifidus, lumbar erector spinae and psoas
transversus abdominis was associated with a
when
compared
with
3
were
conducted
into
the
Further
possible
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
change in intra-abdominal pressure and that the
diaphragm
also
reacted
in
a
Control Subsystem
Neural
feed-forward
manner. Recent studies have also shown coactivation of the transversus abdominis and the
pelvic
floor
muscles,
in
particular
the
pubococcygeus (Sapsford et al 2001).
Biomechanical models which are aligned to
the segmental stabilization model.
These
concepts,
which
formed
the
Passive subsystem
Spinal column
initial
Active subsystem
Spinal muscles
Figure 1: The three subsystems which contribute to
active spinal stabilization. Reproduced from
Richardson et al 1999
versions of the segmental stabilization model,
were supported by two pioneering studies of the
time in the area of biomechanics. The main
For example, it was hypothesized that injury to
researcher who shaped the direction of the
the passive system could be compensated for
exercise model was Manohar Panjabi.
by the muscle system. This gave a rationale
for why specifically directed exercise aimed at
In
1992,
Panjabi
introduced
an
innovative
enhancing joint stability could be effective in
biomechanical model dealing with the function
relieving joint pain.
of the spinal stabilization system. The model
incorporated a passive subsystem, an active
In addition, Bergmark in 1989, had suggested,
subsystem and a control subsystem (Fig 1).
based on his biomechanical model, that the
skeletal muscle system could be broadly divided
The passive subsystem included the osseous
into two separate systems, the local and global
and
muscle
articular
structures
and
the
spinal
systems.
Using
Bergmark's
ligaments. The active subsystem referred to the
classification, the local muscle system included
spinal muscles, which are under the control of
deep muscles and the deep portions of some
the neural control subsystem to provide spinal
muscles which have their origin or insertion on
stability.
the lumbar vertebrae. These local muscles, it
was
argued,
controlled
the
stiffness
and
An important feature of the model that has
intervertebral
relationship
influenced the development of the motor control
segments.
contrast,
programme was the hypothesis that one system
system,
was capable of compensating for another in the
superficial muscles of the trunk, was responsible
case of pathology, pain or injury.
for moving the spine and transferring load
In
encompassing
the
the
of
the
spinal
global
muscle
large,
more
directly between the thoracic cage and pelvis.
4
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
These
biomechanical
models
encouraged
relationship
between
transversus
abdominis,
researchers to look more closely at the function
multifidus and the deep fascial system which
of the local muscle system in relation to the
surrounds the lumbopelvic region. Transversus
development and treatment of musculoskeletal
abdominis,
injuries such as mechanical low back pain. The
thoracolumbar
new direction for our research has been based
abdominal fascia anteriorly, appears to exert its
on
models which
effect on spinal stability through the fascial
explain the close link between the segmental
system. Our research is demonstrating that
stabilization model of exercise and safe and
dysfunction in this musculofascial system is
efficient weight-bearing function.
closely related to the presence of low back pain.
2.3
some new
biomechanical
The segmental stabilization
exercise for weight bearing
model
its
fascia
insertion
posteriorly
to
the
and
the
The importance of the concept of the deep
of
The local muscle system has been implicated in
with
muscle corset for the support of the lumbopelvic
The segmental stabilization model of exercise for weigh
region has come through the clinical use of real-
providing the stiffness of the joints of the
time ultrasound (Hides et al 1998) and our
lumbopelvic region for both movement and
current research, involving the use of magnetic
weight-bearing
based
resonance
imaging
treatment of the local muscle system (Hides et
techniques
have
al 1996, 2001, O'Sullivan et al 1997) has
musculofascial system to be viewed in its
demonstrated
normal and dysfunctional state.
function.
that
the
Evidence
exercise
which
is
(MRI).
These
allowed
imagining
the
deep
effective in the management of low back pain
involves teaching patients to form a dynamic
In selected pain-free individuals, a muscular
muscle
'corset'
contraction
of
corset is formed automatically in response to a
multifidus.
We
simple instruction to pull in the lower abdomen
believe that this corset system offers support to
(without spinal movement occurring). Figure 2
the region due to the close relationship between
gives a diagrammatic interpretation, taken from
the
and
MRI data, of the deep musculofascial corset
multifidus, with the fascial system (and joint
which is formed with this instruction. This deep
structures) of the lumbar spine and pelvis. It is
muscle
our contention that it is this deep, dynamic
muscle shortening of each side of transversus
muscular
abdominis, does not
transversus
involving
abdominis
muscles,
corset
and
transversus
which
abdominis
provides
the
basic
support of the skeleton for weight bearing.
contraction,
The deep muscular corset
One of the most important aspects of the local
function
(and
dysfunction)
is
occur in
symmetrical
response to
drawing in the abdominal wall in patients with
low back pain.
muscle
involving
the
5
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
The function of transversus abdominis and
multifidus: providing joint stiffness for
weight bearing through the lumbar spine
The
studies
of
Keifer
et
al
(1997,
1998)
addressed the issue of integration between local
and
global
muscles
and
emphasized
the
importance of the relationship between spinal
curves, spinal loading and muscle recruitment.
The
studies
(passive
used
a
finite
element
model
osseoligamentous
spine)
with
optimization of the muscles (active and passive
components of muscle force). In the first study,
Figure 2: A diagrammatic representation of the
'deep muscle corset'. Reproduced from Richardson
et al 1999
Keifer et al (1997) loaded the spine without the
muscles using compressive axial forces. They
demonstrated
Similarly, the multifidus is also capable of
fascia
was
investigated
which
by
It
was
proposed
in
the
involve
local
loads
Pelvic rotation (anterior tilt) stiffened the spine,
and only 2 degrees of anterior rotation allowed
to improve segmental
increasing
physiological
withstand compressive forces without buckling.
thus tensioning it and increasing the stiffness of
stabilization
than
model increased the ability of the spine to
muscles exerts a pushing force on the fascia,
Exercises
less
Addition of local and global muscles into the
hydraulic
amplifier mechanism that contraction of the
the spine.
are
(indicated by displacement of the T1 vertebra.)
Gracovetsky et al (1977) using a mathematical
model.
the thoracolumbar spine
translates into hyper-mobility under axial loads
contributing to the changing tension in the
thoracolumbar
that
the spine to carry axial compression of up to
muscle
400
activation to tension the fascia, often with the
newtons,
with
only
7mm
of
anterior
displacement of T1. There was less anterior
assistance of real-time ultrasound to assess and
displacement
train deep muscle control (Richardson et al
of
T1
with
local
and
global
muscles incorporated into the model than with
1999). In order to develop and explain the role
global
of the deep, dynamic muscle corset in relation
muscles
alone,
highlighting
the
importance of integration of the two muscle
to weight bearing, it is important to review the
systems.
biomechanical models that have been devised in
relation to weight bearing through the spine as
In
well as weight bearing through the pelvis.
the
second
study,
Keifer
et
al
(1998)
investigated the synergy of the spine in neutral
positions. Using the same model they displaced
T1 40mm anteriorly and 20mm posteriorly.
6
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
Results
demonstrated
that
for
very
small
pelvis. The model predicts that the action of the
displacements, the global muscles and passive
transverse fibres of pelvic muscles such as
structures are sufficient to stabilize the spine.
transversus
However, the system is far more efficient with
piriformis can stiffen the sacroiliac joints (i.e.
inclusion of the local muscles in the global
force closure) and stabilizes the pelvis for
system, provided stiffness, increased stability
weight bearing (this is similar to the effects of a
and increased compression. Considering the
belt around the pelvis). Thus a key function of
contribution of the local muscles, 80% was
these transverse muscles for the pelvis is likely
provided by multifidus, with some contribution
to be the control of weight bearing through the
by iliocostalis. Another finding was that the
lumbopelvic region (Fig 3).
abdominis,
ischiococcygeus
and
position of the thoracolumbar junction was
important. If T12 was held back, then the upper
lumbar spine was forced into flexion and the
synergy was disturbed. This had a resultant
marked effect on the distribution of intersegmental rotations, and lessened the capacity
of
the
passive
system
to
carry
sagittal
moments.
This model of spinal loading has resulted in the
increased emphasis on the importance of the
Figure 3:
The transverse muscle force which
compresses the sacroiliac joint surfaces to help
prevent sharing due to vertical (weight-bearing) force
(F). Reproduced from Snijders et al 1995
neutral spine position for weight bearing, as well
as its importance as an optimal position for the
integration of the local
and global muscle
Our
function.
recent
study
biomechanical
The function of transversus abdominis and
the deep pelvic muscles: providing joint
stiffness for weight bearing through the
pelvis
contraction
of
demonstrated
effect
of
an
transversus
that
the
independent
abdominis
and
lumbar multifidus (elicited through instructing
the subjects to pull in the abdomen without
The biomechanical aspects of weight bearing in
moving the spine) on the laxity of the sacroiliac
the lumbopelvic region have been extensively
joints (Richardson et al 2002).
researched by Snijders and colleagues (1995).
laxity was measured using Doppler imaging of
They developed models to explain how the
vibrations.
pelvis and the sacroiliac joints can resist shear
transversus
from the force of gravity as well as resisting the
(confirmed
extremely high forces developed by the skeletal
electromyography)
muscles which have large attachments to the
decreased laxity) of the sacroiliac joints to a
7
A
Sacroiliac joint
specific
contraction
abdominis
and
using
real-time
increased
of
the
multifidus
ultrasound
and
stiffness
(or
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
greater degree than a higher level 'bracing'
released, and the muscles measured using
contraction involving all the muscles of the
electromyography (EMG). Reaction time was
abdominal
compared between the two groups. Results
wall.
These
results
confirm
the
biomechanical model of the mechanics of the
showed
that
sacroiliac joint by Snijders et al (1995), which
agonistic
proposed that the transversely oriented muscles
antagonists. In contrast, LBP patients exhibited
such as transversus abdominis are well suited
a
for a role of increasing the stiffness of the
remaining active while the antagonists switched
sacroiliac joints for weight bearing but that the
on.
superficial abdominals are not as efficient. This
mechanism to support the lumbar spine.
muscles
pattern
This
controls
of
quickly
and
switched
co-contraction,
may
have
shut
been
with
a
off
the
on
the
agonists
compensation
study has provided some initial evidence of how
the transversus abdominis can directly help to
Another study has also indicated that global
stabilize and control
the pelvis for weight
muscles are used more in back pain patients.
bearing and also explains how specific activation
Ng et al (2002) demonstrated higher activation
of the deep local muscles could exert an effect
levels and decreased fatigability of the right
on pain and pathology of the sacroiliac joints.
external
oblique
muscles
in
chronic
LBP
patients, suggesting that the global muscles
Poor patterns of weight bearing
may be used to compensate for poor segmental
The study by Richardson et al (2002) also
stability. As suggested by Keifer et al (1997,
demonstrated that a 'bracing co-contraction'
1998) and Richardson et al (2002), increasing,
pattern involving global muscle contraction of all
global muscle activity may not be the most
the abdominals and erector spinae was less
efficient
efficient in producing stiffness of the sacroiliac
lumbopelvic region, especially in weight bearing.
strategy
for
stabilization
of
the
joints that the deep corset action. Interestingly
there is some evidence that such co-contraction
Thus the segmental stabilization
patterns are associated with low back pain. An
weight bearing focuses on exercises for the
important
investigated
deep muscle system and also addresses the
recruitment of global muscles in LBP patients
increased activity of the global system. Specific
was conducted by Radebold et al (2000). In this
exercise
study, a quick release method in four directions
contractions
of isometric trunk exertions was used to study
combined
muscle response patterns in LBP patients and
recruitment of the global muscles. Details of
matched controls. Subjects were placed in semi-
these techniques have been described in detail
seated position in an apparatus that fixated the
in the text by Richardson et al (1999).
study
which
has
pelvis. They performed isometric exertions of
the trunk, the resisted force was suddenly
8
techniques
of
with
the
involve
local
methods
model for
retraining
muscle
to
the
system
decrease
the
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
2.4
A de-loading model was designed (in a non-
The antigravity muscle system for
high load function
weight bearing prone position) to study the
muscle synergists of the knee during fast
To explain the further development of this
(phasic) lower leg movement where feedback
weight bearing, antigravity model of exercise, it
from gravitational load cues was minimized
is necessary to first differentiate the synergists
(Richardson & Bullock 1986). A specifically
into local and global muscle sub groups of
positioned spring (Fig 4) calibrated to the
mono-articular and multi-articular categories.
weight of the individual's lower leg, was used to
'Mono-articular' refers to muscles which span a
de-load the muscle system.
single joint (or one area of the spine) and are
capable of generating high joint torque as well
as controlling a single joint position. The second
category,
the
'multi-joint/multi-function'
muscles, is the antithesis of this group. These
muscles cross over more than one joint (or one
area of the spine), are usually more superficial,
perform multiple functions at multiple joints and
are more aligned to efficient movement rather
than joint protection and stability. It will be
argued
that
the
local
and
mono-articular
muscles work together to form an efficient
Figure 4: The exercise model used a spring
attachment to minimize the effect of gravity on
the lower leg. Reproduced from Richardson et
al 1999
'antigravity' system with the multi-joint /multifunction muscles aligned to a movement role
with minimal contribution to the opposition of
the force of gravity in weight-bearing positions.
Muscle recruitment patterns were investigated
This
through studying changes in levels of muscle
gravity
related
hypothesis
has
been
developed through research using models of de-
activation
loading or microgravity environments where
cycles) in slow, medium and fast speeds of
gravity has been minimized or eliminated.
lower
leg
(total
EMG
movement.
for
three
High-speed
movement
repetitive
movement is known to be pre-programmed and
Change
in
the
recruitment
of
the
antigravity muscle system with de-loading
of the skeleton
The
gravity
developed
patterns
related
from
and
hypothesis
studying
muscle
the
has
not to rely on sensory feedback. Thus this deloading model not only reduced gravitational
load via a spring, it also resulted in reduced
been
proprioceptive feedback due to the nature of the
recruitment
physiology
task.
changes
occurring with de-loading of the skeleton.
9
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
The results proved to be very significant. The
and load cues. These issues, as they relate to
multi-joint
and
the lumbopelvic region, have become the focus
hamstrings contracted in a phasic pattern with
of our research direction in relation to the
the movement and increased their activation
expanded exercise concept of proprioceptive
levels significantly with increases in speed. The
antigravity training.
muscles,
rectus
femoris
local muscle, vastus medialis oblique, as well as
the mono-articular muscle, vastus lateralis, did
We believe that research into the problems
not increase their activation levels over the
which develop from de-loading the skeleton has
increasing speeds. This finding highlighted their
important implications for the way exercise is
antigravity role, rather than a movement role as
used to promote the functional integration of
demonstrated in the multi-joint muscles. In
the local, mono-articular and multi-joint muscle
addition in 90% of cases the vastus medialis
systems. Long-term de-loading of the skeleton,
oblique, and in 45% of cases the vastus lateralis
which
demonstrated a tonic, continuous response to
removed,
the phasic lower leg movement. This would
patterns
seem to indicate that these muscles do not
system. These patterns consist of an increase in
respond to movement cues but rather require
recruitment of muscles designed for movement
proprioceptive feedback, including gravitational
and a reduced recruitment in the muscles
load cues for their recruitment into functional
involved in the control of gravitational load.
movement.
Thus integration of the local muscle system
must
occurs
when
results
of
occur
gravitational
in
predicted,
neuroplasticity
in
weight
of
bearing
load
is
consistent
the
nervous
where
the
The knee musculature has been extensively
antigravity muscles work together to protect
investigated in space (microgravity) research in
joints from injury. Weight bearing (closed chain)
both
Similar
exercise is the key to rehabilitation as the multi-
recruitment patterns are demonstrated when
joint (movement) muscles are not required in
gravitational
While
exercise joints flexed. The design of the weight-
non-weight-bearing
bearing exercise has been streamlined by the
animal
marked
vastus
and
human
load
atrophy
cues
of
medialis
studies.
are
the
(local)
and
absent.
weight-bearing
previously
described
biomechanical
models
vastus lateralis (mono-articular) occurs, there is
which have linked gravitational load, the pelvis
no
and spinal posture with muscle function.
change
in
the
size
of
the
multi-joint
hamstrings and rectus femoris (see Richardson
2002 for review). This would further support the
hypothesis that multi-joint muscles are closely
linked to movement but not gravitational load,
while
the
local
and
mono-articular
have
antigravity roles and respond to gravitational
10
The rationale for a motor control programme for the treamtment of spinal muscle
dysfunction
__________________________________________________________________
2.5
'corset action' of the deep local muscle system
Widening perspectives for segmental
stabilization to a more functional
proprioceptive
antigravity
training
model
is considered essential to increase stiffness of
both the lumbar spine and pelvis in preparation
for weight bearing. In this regard, it is the
The segmental stabilization model has now been
further
refined
and
evolved
through
neutral spine, most particularly the lumbar
new
lordosis, which is important for training weight-
information in the areas of motor control and
bearing function. For the integration of the
biomechanics related to weight bearing. This
overall
gravity
focus
has
led
to
antigravity system (i.e. local and one-joint
the
muscles) into function, the most important
proprioceptive antigravity training model. Most
aspect of training is to increase the sensory load
importantly, in the area of motor control,
muscle
recruitment
patterns
have
cues in weight bearing are simulated weight
been
bearing, while ensuring that the local and one-
investigated in relation to the influence of
joint muscles are responding to gravitational
gravity. It is gravitational physiology research,
including
research
into
the
motor
(sensory)
control
load
contraction
problems which develop from de-loading the
cues
of
and
the
there
is
minimal
multi-joint/multifunction
muscles during the training.
skeleton, which is forming the foundation for
the development of exercise strategies used to
Our new research stream is currently being
promote the functional integration of the local
and
global
muscle
systems.
The
developed through microgravity research, which
muscle
will allow us to further understand the function
recruitment patterns are closely linked to two
biomechanical
weight-bearing
and dysfunction of the lumbopelvic muscle
models,
synergists in relation to de-loading (as well as
addressing both the pelvis and the spine, which
explain
how
the
body
deals
best
injury
with
and
pain).
More
importantly,
our
continued research is investigating the most
gravitational forces in a weight-bearing exercise
efficient
method which minimizes the more active multi-
motor
joint (movement) muscle system. Thus research
exercise
control
counter-measures
problems
in
the
for
the
antigravity
musculature.
in both biomechanics and motor control are
influencing
the
evolution
of
the
training
ABOUT THE AUTHORS
programme.
Carolyn A Richardson, BPhty (Hons) PhD
Associate Professor and Reader, Department of
Physiotherapy,
University
of
Queensland,
Brisbane, Australia
As explained in previous sections, there are
several
important
changes
in
direction
for
Julie A Hides, BPhty MPhtySt PhD
Senior Lecturer, Department of Physiotherapy,
University of Queensland, Brisbane, Australia
rehabilitation which have been based on the
described
rationale
for
the
weight-bearing,
antigravity model of exercise. Activating the
11