Assessment of pelvic floor of women runners by three-dimensional ultrasonography and surface electromyography. A pilot study.
To evaluate female runners' pelvic floor muscles using three-dimensional ultrasonography (3DUS) and surface electromyography (SEMG). A cross-sectional study was conducted on 24 female runners. SEMG was performed using surface electrodes inserted in the vagina. 3DUS was performed using perineal convex transducer. SEMG was evaluated at rest and with maximum voluntary contraction (MVC) and slow contraction. Levator ani muscle thickness, levator hiatus area and the angle between the levator muscles at rest and with MVC and Valsalva were evaluated using 3DUS. The women were divided into two groups (women running </= 25 km/week; women running > 25 km/week). Means, standard deviations and non-paired t tests were used for both groups. Among the 24 women, 11 ran </= 25 km/week (16.91 +/- 4.13 km/week) and 13 ran > 25 km/week (40.77 +/- 1.15 km/week). The mean SEMG at rest and with MVC and slow contraction were 16.25, 65.86 and 71.41 mV, respectively. For the levator hiatus area at rest and with MVC and Valsalva, the means were 12.54, 10.06 and 16.57 sqcm, respectively. Correlations between 3DUS and SEMG showed significant differences in SEMG at rest and levator thickness with Valsalva (r = 0.46; p = 0.04). 3DUS and SEMG are two feasible methods for evaluating female runners' pelvic floor. Correlations between 3DUS and SEMG showed significant differences in SEMG at rest and levator thickness with Valsalva.