The Feasibility of Using an Intravaginal Intra-Abdominal Pressure Sensor During Running to Evaluate Pelvic Floor Loading and Its Association with Running-Induced Stress Urinary Incontinence: An Observational Cohort Study.

INTRODUCTION AND HYPOTHESIS

The aim was to investigate the feasibility of using an intravaginal intra-abdominal pressure (IAP) sensor worn by female runners during running to evaluate pelvic floor loading, and the association between IAP and running-induced stress urinary incontinence (RI-SUI).

METHODS

Twenty-eight female runners participated in this cross-sectional study (15 with RI-SUI and 13 continent). Participants completed a 37-min treadmill running protocol instrumented with an intravaginal sensor measuring IAP, and a skin-mounted accelerometer measuring pelvic accelerations. Linear regression analyses evaluated the relationship between IAP and pelvic acceleration. One-way ANOVAs assessed the impact of running speed on IAP. Sensor dislodgement was recorded, and effect sizes (Cohen's d) were calculated for the comparison of IAP and accelerometry outcomes between runners with and without RI-SUI.

RESULTS

Intra-abdominal pressure showed high variance and the sensor was expelled in almost 15% of participants. Positive associations were found between pelvic acceleration and both absolute peak and normalized IAP but explained only between 12% and 18.6% of the variance in the models. Pelvic acceleration during running was not associated with cumulative IAP. Peak IAP significantly increased with running speed. Although IAP tended to be higher in runners with RI-SUI than in continent runners (Cohen's d between 0.14 and 0.74), pelvic accelerations tended to be lower (Cohen's d between 0.02 and 0.55).

CONCLUSIONS

There is high variance in IAP recorded during running using an intravaginal sensor. Faster speeds increase pelvic floor loading. Runners with RI-SUI may experience higher IAP than continent runners, warranting investigation. Recruitment should include a 15% data loss rate owing to sensor expulsion.