Relationship between aerobic capacity and pelvic floor muscles function: a cross-sectional study

The objective of this study was to evaluate the relationship between aerobic capacity and pelvic floor muscles (PFM) function in adult women. Women aged 18 or over and without urinary dysfunction or other chronic diseases were eligible to participate. They completed the habitual physical activity (HPA) questionnaire, underwent a PFM functional evaluation by palpation and perineometry, and performed a submaximal (between 75 and 85% of maximum heart rate) cardiopulmonary exercise (CPX) test to determine the ventilatory anaerobic threshold (VAT). Forty-one women were included (35±16 years, 75% physically active, 17% very active, and 8% sedentary and 17% presented grade 1 PFM contraction, 31.8% grade 2, 26.8% grade 3, and 24.4% grade 4, according to the modified Oxford Scale). The average PFM contraction pressure obtained by perineometer was 53±26 cmH(2)O and the average oxygen consumption at VAT (VO(2)VAT) obtained from CPX was 14±2 mL·kg(-1)·min(-1). Significant correlations were found between PFM contraction pressure and VO(2)VAT (r=0.55; P<0.001); between PFM contraction pressure and HPA score (r=0.38; P=0.02); between age and VO(2)VAT (r=-0.25; P=0.049); and between VO(2)VAT and HPA score (r=0.36; P=0.02). An age-adjusted multiple linear regression equation (R(2)=0.32) was derived to estimate VO(2)VAT from the contraction value obtained by perineometer, so that the PFM contraction pressure was able to predict VO(2)VAT. The equation was validated using data from another group of 20 healthy women (33±12 years; PFM contraction: 49±23 cmH(2)O) and no significant difference was found between actual VO(2)VAT and predicted VO(2)VAT (13.1±1.9 vs 13.8±2.0 mL·kg(-1)·min(-1)). In conclusion, PFM function is associated with aerobic capacity in healthy women and PFM contraction pressure may be used to estimate VO(2)VAT in this population.