Effects of Indirect Pelvic Floor Muscle Activation Exercise Using a Pressure Biofeedback Unit on Trunk Muscle Activity in Sitting Position

Effects of Indirect Pelvic Floor Muscle Activation Exercise Using a Pressure Biofeedback Unit on Trunk Muscle Activity in Sitting Position

Background: Exercise for pelvic floor muscles (PFMs) is an effective intervention method to reduce urinary incontinence. The PFMs maintain trunk stability by improving intra-abdominal pressure by co-contracting with the transverse abdominis (TrA), multifidus (MF), and diaphragm muscles. Purpose: This study investigated the effect of indirect PFMs activation using a pressure biofeedback unit (PBU) on trunk muscle activity in a sitting position. Study design: Cross-sectional Study. Methods: A total of 20 healthy female participants were recruited for this study. Surface electromyography (EMG) was used to measure TrA/internal abdominal oblique (IO), MF, external abdominal oblique (EO), and rectus abdominis (RA) activity during PFMs activation. EMG was used to measure trunk muscle activity under three conditions: before exercise, immediately after exercise, and after 10 min of exercise. The mean value of trunk muscle activity under each of three conditions was analyzed by a one-way repeated measures analysis of variance. A post hoc test was used to compare significant differences between each set of conditions. Results: A significant increase in muscle activity (%maximal voluntary isometric contraction) of the TrA/IO, MF, EO, and RA was observed immediately after indirect PFMs activation exercise (p<0.01). After 10 min of PFMs activation, significant increases in TrA/IO and MF muscle activity was observed. Conclusions: These results indicate that indirect PFMs activation in a sitting position using a PBU may be beneficial for increasing stabilization of the trunk and PFMs, specifically the TrA/IO muscles.