Healthy adults can more easily elevate the pelvic floor in standing than in crook-lying: an experimental study.

QUESTIONS Are there any differences in the displacement and endurance of an elevating voluntary pelvic floor muscle contraction in standing and in crook-lying? Are there any differences in these variables between males and females in either test position? DESIGN An experimental study. PARTICIPANTS Forty-five nulliparous female and 20 male participants aged 23 years (SD 3) with no symptoms of urinary incontinence or low back pain. INTERVENTION Voluntary pelvic floor muscle contraction was measured in both standing and crook-lying. OUTCOME MEASURES Transabdominal ultrasound was used to measure the displacement (mm) and endurance (s) of pelvic floor elevation. RESULTS Displacement was greater in standing than in crook-lying (mean difference 2.6 mm, 95% CI 1.5 to 3.7). There was no difference between males and females (mean difference 1.3 mm, 95% CI 0.5 to 3.2). Similarly, endurance of pelvic floor elevation was longer in standing than in crook-lying (mean difference 17.3 s, 95% CI 12.2 to 22.4). Again there was no difference between males and females (mean difference 0.5 s, 95% CI 9.3 to 8.3). CONCLUSION Standing was found to be a more effective position for achieving and sustaining an elevation of the pelvic floor compared to crook-lying, regardless of sex, and this should be taken into account when assessing and training pelvic floor muscle contraction.