Effects of Co-contraction of Both Transverse Abdominal Muscle and Pelvic Floor Muscle Exercises for Stress Urinary Incontinence: A Randomized Controlled Trial

[Purpose] The purpose of this study was to devise a new urinary incontinence exercise using co-contraction of both the transverse abdominal muscle (TA) and pelvic floor muscle (PFM) and examine the intervention effect in middle-aged women with stress urinary incontinence (SUI). [Subjects] The subjects were fifteen women with SUI who were divided into two groups: the TA and PFM co-contraction exercise group (n=9) and the control group (n=6). [Methods] Participants in the exercise group performed TA and PFM co-contraction exercise. The thickness of the TA was measured before and after 8 weeks of exercise using ultrasound. The thickness of the TA was measured under 4 conditions: (1) at rest, (2) maximal contraction of the TA, (3) maximal contraction of the PFM, and (4) maximal co-contraction of both the TA and PFM. [Results] There were no significant differences among the results of the control group. In the exercise group, the cure rate of SUI was 88.9% after the intervention. There were significant differences in the thickness of the TA during maximal co-contraction of both the TA and PFM after the intervention. [Conclusion] The TA and PFM co-contraction exercise intervention increases the thickness of the TA and may be recommended to improve SUI in middle-aged women.