Ultrasound measurement of abdominal muscles activity during abdominal hollowing and bracing in women with and without stress urinary incontinence

Synergistic co-activation of the abdominal and pelvic floor muscles (PFM) has been reported in the literature. Considering that PFM dysfunction is present in women with stress urinary incontinence (SUI), altered abdominal muscle activation may also occur in incontinent women. The purpose of this study was to investigate the abdominal muscle activity during abdominal hollowing and bracing maneuver in women with and without SUI using ultrasound. Convenience sample of 20 non-pregnant female participated in the study. Subjects were categorized into two groups: continent females (N = 10) and females with SUI (N = 10). The percentage of change in thickness of right transverse abdominals (TrA) and internal obliques (IO) was measured during abdominal hollowing and bracing maneuver in both groups. The result of two-way mixed-design ANOVA revealed no significant health status by maneuver interaction effect for ultrasound measurement of the percentage of change in thickness of TrA (P = 0.66) and IO (P = 0.36). The main effect of health status on the percentage of the change in thickness of TrA (P = 0.52) or IO (P = 0.84) was not statistically significant. In overall, no significant difference was found in the percentage of changes in thickness of TrA and IO muscles during abdominal hollowing or bracing maneuver between women with and without SUI.