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Sitting posture affects pelvic floor muscle activity in parous women: an observational study
Ruth R Sapsford1, Carolyn A Richardson, Warren R Stanton
1Department of Physiotherapy, Mater Misericordiae Hospital, Brisbane, QLD, Australia. rsapsford@ozemail.com.au
Question:
Do different sitting postures require different levels of pelvic floor and abdominal muscle activity in healthy women?
Design:
Observational study.
Participants:
Eight parous women with no pelvic floor dysfunction.
Outcome Measures:
Bilateral activity of pelvic floor muscles (assessed vaginally) and two abdominal muscles, obliquus internus abdominis and obliquus externus abdominis, during three sitting postures.
Results:
There was a significant increase in pelvic floor muscle activity from slump supported sitting (mean 7.2% maximal voluntary contraction, SD 4.8) to both upright unsupported sitting (mean 12.6% maximal voluntary contraction, SD 7.8) (p = 0.01) and very tall unsupported sitting (mean 24.3% maximal voluntary contraction, SD 14.2) (p = 0.004). Activity in both abdominal muscles also increased but did not reach statistical significance.
Conclusion:
Both unsupported sitting postures require greater pelvic floor muscle activity than the supported sitting posture.
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