Authors: Diane E. Gregory and Jack P. Callaghan
The use of stability balls in the workplace in place of the standard office chair (PDF)
The
stability
ball
is
a
large
(diameter
ranging
from
60
to
100cm)
inflated
ball
primarily
used
for
core
stabilizing
exercises
such
as
abdominal
crunches
and
back
extensor
exercises3,13.
Stability
balls
are
also
often
used
in
rehabilitation
settings
to
aid
in
whole
body
balance
development
and
control.
However,
recently,
their
popularity
as
an
alternative
to
the
standard
office
chair
has
risen.
Stability
ball
manufactures
claim
that
using
the
ball
in
place
of
an
office
chair
has
benefits
such
as
increased
trunk
muscle
activation
and
thus
increased
core
strength,
improved
posture,
and
decreased
discomfort.
The
claim
of
decreased
discomfort
is
based
on
research
that
has
shown
a
positive
relationship
between
reduced
trunk
muscle
strength
and
individuals
with
low
back
pain1,6.
However
conflicting
research
has
reported
no
relationship
between
strength
and
low
back
pain2.
Other
research,
however,
points
to
reduced
trunk
muscle
endurance,
not
strength,
as
being
a
better
indicator
of
which
individuals
report
low
back
pain7.
It is well accepted that more neutral spine postures during workplace exposures may reduce the development of low back pain11. These ideas suggest that if the claims made by stability ball companies are in fact correct, then the stability ball may have some potential to decrease and/or prevent low back pain associated with prolonged seated work. However, prolonged exposure to increased muscle activation may also be detrimental to individuals, as research has shown that muscle activation with few rest breaks, over extended periods, can result in localized muscle pain or overload5,12.
Prior
to
the
work
conducted
at
the
University
of
Waterloo,
no
study
has
ever
directly
compared
the
trunk
muscle
activation
and
spine
posture
of
individuals
while
sitting
on
a
stability
ball
to
those
on
a
standard
office
chair.
However,
anecdotal
evidence
suggests
that
while
initial
use
of
a
stability
ball
as
a
chair
may
induce
low
back
pain,
progressive
use
may
actually
help
reduce
low
back
symptoms
after
the
user
has
accommodated
to
using
a
ball
as
a
chair9.
A
recent
study
by
O’Sullivan
and
colleagues10
examined
differences
in
trunk
muscle
activation
and
spine
posture
while
sitting
on
the
SitFit™,
an
air
filled
cushion
that
is
placed
on
top
of
the
users
seat
pan
with
similar
claims
to
stability
ball
manufacturers,
as
compared
to
a
standard
office
chair
for
a
short
five
minute
duration
of
sitting.
While
they
found
no
differences
in
trunk
muscle
activation,
spinal
lordosis,
or
pelvic
tilt,
they
did
observe
increased
spinal
sway
while
on
the
SitFit™;
however
this
may
simply
be
participants
getting
settled
on
the
device
given
the
short
duration
of
the
seated
exposures.
The
first
study
conducted
in
Dr
Jack
Callaghan’s
lab4
examined
trunk
muscle
activation
patterns
and
lumbar
spine
posture
in
14
healthy
men
and
women
while
sitting
on
a
stability
ball
for
one
hour,
and
in
a
standard
office
chair
for
one
hour,
presented
in
random
order.
Results
showed
no
significant
differences
between
the
muscle
activation
patterns
while
on
the
ball
versus
the
chair
with
the
exception
of
the
left
thoracic
erector
spinae
muscle,
which
could
be
attributed
to
handedness
and
workplace
interaction
while
sitting
on
different
surfaces.
Further,
increased
discomfort
in
both
the
low
back
and
buttocks
region
was
reported
by
all
individuals
while
sitting
on
the
ball
as
compared
to
the
chair.
A
similar
study
conducted
in
Dr
Stuart
McGill’s
lab8
further
examined
muscular
activation
patterns
and
lumbar
spine
posture
while
sitting
on
a
stability
ball,
but
compared
it
to
sitting
on
a
standard
wooden
stool.
This
study
also
found
no
significant
differences
in
muscle
activation
and
lumbar
spine
posture.
Further,
this
study
had
the
added
advantage
of
the
quantification
of
low
back
compression
and
spine
stability
while
sitting
on
the
two
surfaces
but
found
no
differences
in
the
magnitude
of
these
measures
between
the
ball
and
stool.
Both
these
studies
employed
individuals
who
were
not
habitual
users
of
balls
as
office
chairs
and
no
accommodation
training
was
provided.
Conclusion
Given the results of the work conduced at Waterloo, it appears as though there are no benefits to sitting on a stability ball as compared to a standard office chair and claims made by stability ball manufactures, as stated above, were disproved by the current work. Over a prolonged period of sitting (one hour) no differences in trunk muscle activation patterns were observed, suggesting the ball does not aid in core strengthening, and no differences were found in lumbar spine posture, suggesting that the ball does not actually invoke an improved posture. Moreover, the most important finding of these studies was that individuals actually complained of more discomfort when sitting on the stability ball – disproving the final claim made by manufactures.
Key messages
- Stability balls do not provide any inherent benefits in the absence of other physical training and workstation interventions
- Over a prolonged period of sitting (one hour) no differences in trunk muscle activation patterns were observed, suggesting the ball does not aid in core strengthening
- The ball does not actualy provoke an improved posture as no differences were found in lumbar spine posture
- Individuals complained of more discombort when sitting on the stability ball
- Use of ball as a chair may increase the risk of developing low back discomfort and increase the risk of sustaining an injury due to the unstable nature of these balls.
Implications for the prevention of MSD
It is of the authors’ opinions that stability balls should not be used as an alternative to the standard office chair since the device itself, in the absence of other physical training and workstation interventions, does not seem to provide any inherent benefits to the end user. Further, using the stability ball as a chair may actually increase the risk of developing low back discomfort and may increase the risk of sustaining an injury due to the inherent unstable nature of these balls.
References
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- Biering-Sorensen, F. (1984) Physical measurements as risk indicators for low-back trouble over a one-year period. Spine 9(2), 106-119.
- Drake, J.D., Fischer, S.L., Brown, S.H., Callaghan, J.P. (2006) Do exercise balls provide a training advantage for trunk extensor exercises? A biomechanical evaluation. Journal of Manipulative and Physiological Therapeutics 29(5), 354-362.
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- Jonsson, B. (1982) Measurement and evaluation of local muscular strain in the shoulder during constrained work. Journal of Human Ergology 11(1), 73-88.
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- Luoto, S., Helivaara, M., Hurri, H., Alaranta, H. (1995) Static back endurance and the risk of low-back pain. Clinical Biomechanics 10(6), 323-324.
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- O’Sullivan, P., Dankaerts, W., Burnett, A., Straker, L., Bargon, G., Moloney, N., Perry, M., Tsang, S. (2006) Lumbopelvic Kinematics and Trunk Muscle Activity During Sitting on Stable and Unstable Surfaces. Journal of Orthopaedic & Sports Physical Therapy 36, 19-25.
- Punnett, L., Fine, L.J., Keyserling, W.M., Herrin, G.D., Chaffin, D.B. (1991) Back disorders and non-neutral trunk postures of automobile assembly workers. Scandinavian Journal of Work Environment and Health 17, 337–346.
- Veiersted, K.B., Westgaard, R.H., Andersen, P. (1990) Pattern of muscle activity during stereotyped work and its relation to muscle pain. International Archives of Occupational and Environmental Health, 62, 31-41.
- Vera-Garcia, F.J., Grenier, S.G., McGill, S.M. (2000) Abdominal muscle response during curl-ups on both stable and labile surfaces. Physical Therapy 80(6), 564-569
Last updated: 2016
Disclaimer: Position papers are funded by the Centre of Research Expertise for the Prevention of Musculoskeletal Disorders, which receives funding through a grant provided by the Ontario Ministry of Labour. The views expressed are those of the authors and do not necessarily reflect those of the Centre nor of the Province.