Abstract
Sapsford RR, Richardson CA, Maher CF, Hodges PW. Pelvic floor muscle activity in different
sitting postures in continent and incontinent women.
Objective
To determine whether resting activity of the pelvic floor muscles (PFMs) and abdominal
muscles varied in different sitting postures in parous women with and without stress
urinary incontinence (SUI).
Design
PFM and abdominal muscle activity was recorded in 3 sitting postures: slump supported,
upright unsupported, and very tall unsupported. Spinal curves were measured in slump
supported and upright unsupported.
Setting
A research laboratory.
Participants
Women (N=17) with a history of vaginal delivery, 8 who were symptomatic of SUI and
9 who were asymptomatic.
Interventions
Not applicable.
Main Outcome Measures
Electromyographic activity of (1) the resting PFM recorded per vaginam with surface
electrodes and (2) superficial abdominal muscles using surface electrodes. Changes
in spinal curves were measured with a flexible ruler.
Results
Electromyographic activity of the PFM increased significantly from slump supported
to upright unsupported postures in both groups (P<.001) but with lower levels of activity in women with SUI (P<.05). PFM activity increased further in very tall unsupported sitting in comparison
with slump supported sitting (P<.001). Obliquus internus abdominis electromyographic activity was greater in upright
unsupported than in slump supported sitting (P<.05), and electromyographic activity of other abdominal muscles was greater in very
tall unsupported than slump supported. Women with SUI had a trend for greater activity
in the abdominal muscles in upright unsupported than asymptomatic women. Asymptomatic
women had a greater depth of lumbar lordosis in upright unsupported sitting than women
with SUI (P=.04).
Conclusions
More upright sitting postures recruit greater PFM resting activity irrespective of
continence status. Further investigation should consider the effect of sitting posture
in rehabilitation.
Key Words
List of Abbreviations:
ANOVA (analysis of variance), BMI (body mass index), PFM (pelvic floor muscle), SUI (stress urinary incontinence)To read this article in full you will need to make a payment
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Article info
Footnotes
Supported by the National Continence and Women's Health Group of the Australian Physiotherapy Association, and the National Health and Medical Research Council of Australia.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated.
Identification
Copyright
© 2008 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
