The Relationship Between Intra-Abdominal Pressure and Body Acceleration During Exercise

Objectives: High intra-abdominal pressure (IAP) may influence the development of pelvic floor disorders. We and others have used intravaginal pressure transducers to measure IAP in women during exercise and daily activities, but utilizing the transducer for long-term measurements creates compliance issues. Waist-worn accelerometers are prominent in research and may be a reliable alternative for approximating IAP. We hypothesized that there are pair-wise positive correlations between the mean maximal accelerometer vector magnitude and 2 IAP measurements: mean maximal IAP and area under the curve (AUC). Methods: Twenty-five women who regularly participated in exercise performed 13 activities. Intra-abdominal pressure was measured with an intravaginal transducer and acceleration with a waist-worn accelerometer. We determined the mean maximal IAP, AUC for IAP, and mean maximal accelerometer vector magnitude for each activity and participant. The relationship between IAP and acceleration was determined by computing the Pearson correlation coefficient (R) and the 95% confidence interval for mean maximal accelerometer vector magnitude versus mean maximal IAP and mean maximal accelerometer vector magnitude versus AUC for IAP. Results: The R values were 0.7353 for mean maximal accelerometer vector magnitude versus mean maximal IAP (including walking) and 0.5059 for mean maximal accelerometer vector magnitude versus AUC for IAP (excluding walking). Walking at 3 speeds, analyzed separately, presented R values of 0.72208 for mean maximal IAP and 0.21678 for AUC. Conclusion: Waist-worn accelerometers may provide a viable method for approximating mean maximal IAP in a population of women during most activities.