Hypothesis / aims of study
Female athletes have significantly higher prevalence rates of stress urinary incontinence (SUI) than their non-exercising peers.[1] While exercise appears to be protective against many other disease conditions, it may be linked to the development of SUI in an otherwise healthy population. Many female athletes with SUI are nulliparous and lack traditional risk factors for the development of SUI. Research to date has primarily focused on investigating prevalence rates of UI in athletes.[1] While some studies have attempted to determine the risk factors for SUI in the athletic population, initial results have been inconclusive. The purpose of this study was to explore the relationship of sport and athlete characteristics on SUI in nulliparous female collegiate athletes. We hypothesize sport attributes involving higher impact, intensity, and training volume, as well as athlete characteristics such as BMI>25, greater years of sports training, and present or history of disordered eating, will display greater prevalence and impact of SUI.
Study design, materials and methods
A non-experimental study using a cross-sectional survey design was used to explore the research questions. An electronic survey was designed in Qualtrics to female athletes participating in collegiate athletics at three Division II universities. Data collection occurred from January 2021 to February 2021. A small incentive was offered as a recruitment tool. Participants were surveyed on demographics, history of disordered eating practices, sport played and years of involvement, and physical activity levels, intensity, and frequency. The International Consultation on Incontinence Questionnaire-Urinary Incontinence-Short Form (ICIQ UI SF) was used to identify and classify the degree of SUI. All data were analyzed using IBM SPSS Statistics for Windows, Version 27.0 (IBM Corp., Armonk, NY). Mann-Whitney U tests with a p<0.05 were used to indicate statistical significance.
Results
Of athletes surveyed, 35.4% (n=208) reported SUI and 57.4% reported disordered eating practices. The mean age of athletes was 20.19±1.47 years. One hundred eight athletes participated in low or moderate impact level sports and 101 (48.3%) in high impact level sports. Athletes participating in high impact sports demonstrated greater SUI rates and severity than low and moderate impact sports (p=.03). Other variables associated with an increase in SUI were participation in vigorous physical activity >5days/week (p=.037), and a BMI>25 (p=.05). There were no statistically significant results noted for physical activity intensity, training volume, years of training, or disordered eating status. Additional component scores from the ICIQ UI SF can be seen in Table 1.
Interpretation of results
SUI is highly prevalent in the nulliparous female collegiate athlete population with over a third of female athletes affected. Engaging in high-impact athletics and having a BMI>25 appears to be related to SUI, which supports our hypotheses. While SUI scores were not statistically significantly different (p=.057) for athletes participating in high-intensity activities, the results did trend toward significance). Both high impact and high-intensity activity are accompanied by increases in intra-abdominal pressure (IAP) much higher than seen in the general population. When high-intensity exercise was examined in conjunction with exercise frequency, a statistically significant result emerged. Athletes performing intense physical activity six or seven days of the week had greater SUI than athletes performing high-intensity exercise less than six days per week (p=.037).
The high frequency of exposure to IAP may result in a synergic overload to the pelvic floor musculature, decreasing the ability to support the continence mechanism.[2] Athletes with a high BMI or those engaging in high intensity and high impact activity most days of the week have a greater need for pelvic floor muscle training, to strengthen and maintain pelvic floor muscle function to prevent SUI.