Verbal and Visual Feedback Immediately Affect the Electromyographic Activity of Female Pelvic Floor Muscles

Objective: The purpose of this study was to assess the immediate effect of verbal and visual feedback on pelvic floor muscles (PFM) in nulliparous women without pelvic floor dysfunction. Methods: In this observational, single-assessor, cross-sectional study, 45 female university students were evaluated using bidigital vaginal palpation and vaginal surface electromyography (EMG). EMG assessments were performed at 2 time points (T1 and T2). According to the protocol, participants performed 5 maximal voluntary contractions (MVC) with 10-second intervals, 5 sustained voluntary contractions (SVC) for 10 seconds, and a 60-second voluntary contraction until fatigue (CUF) before (T1) and after (T2) receiving verbal instructions and visual feedback on PFM contractions. At T2, women received visual feedback on their PFM contraction. Root mean square (RMS) for each repetition (MVC and VCF) was recorded, and mean value was calculated. Compensatory mechanisms during contraction were recorded visually. The difference in mean RMS (mV) for MVC, SVC, and CUF; curve integral for MVC, SVC, and CUF; median frequency (Hz) for CUF between T1 and T2 were analyzed with repeated measures multivariate analysis of variance. Results: Before the instructions, most participants (95.6%) performed PFM MVC using at least 1 compensatory mechanism. PFM EMG outcomes changed at T2: RMS and curve integral were reduced in T2 (P < .05) for MVC, SVC, and CUF. The median frequency increased from T1 to T2 in the CUF group (P = .01). Conclusion: Verbal and visual feedback had an immediate impact on the EMG activity of PFM in nulliparous continent women.