Regular physical activities, such as walking and exercising, are known to be effective strategies that can prevent various diseases, reduce mortality, and improve one’s quality of life (QOL). Moreover, these physical activities are also closely related to the prevention and improvement of pelvic floor dysfunction because they help maintain an appropriate body weight. In addition, gait function, as measured by the Timed Up Go (TUG) test that assesses gait speed and functional mobility, is a factor that is related to urinary incontinence. Although studies have shown that the number of steps that one has walked (i.e., step count) is negatively related to various health problems, the relationship between step count and urinary incontinence and physical ability remains unclear. Therefore, the purpose of the study was to examine the relationship between step count, urinary incontinence, and physical ability among middle-aged and older women. We hypothesized that step count will be negatively related to urinary incontinence symptoms and positively related to physical ability among middle-aged and older women.

The study used a cohort research design; 20 out of 23 individuals, who participated in a project implemented as part of the Urinary Incontinence Prevention Program during the period of July-December 2018, were included in the study. Three participants were excluded on the basis of the following exclusion criteria: those who had missing data, those with a history of urologic and gynecologic diseases, those who have undergone surgeries in the past, those who were receiving treatment for urologic, gynecologic, or cardiovascular diseases at the time of the study, and those who were judged by doctors as being unsuitable for inclusion in the present study. Participants were required to respond to survey items about basic demographic details (i.e., age, height, weight, Body Mass Index [BMI], number of deliveries, presence or absence of urine leakage during the day and night, frequency of urination per day), the International Consultation on Incontinence Questionnaire-Urinary Incontinence-Short Form (ICIQ-UI SF), and the Skeleton Muscle Mass Index (SMI). Further, information such as the number of steps taken (i.e., step count), metabolic equivalent (METs; i.e., intensity of physical activity), exercise (i.e., amount of physical activity), comfortable walking speed (m/s), maximum walking speed (m/s), and scores on the TUG test were also recorded. Step count was measured for seven days from the date of initiation of the Urinary Incontinence Prevention Program, using a triaxial accelerometer Active Style Pro HJA-750C (OMRON Co., Ltd., Kyoto). Step count and physical activity were calculated on a daily basis; the METs figure was divided by the time taken in order to calculate the average value per unit time. Participants who recorded a step count that was higher than the group mean were classified as the “high step count group” whereas those who scored below the group mean were classified as the “low step count group.” Version 2.8.1 of the statistical software “R” was used to compare these two groups on each of the study variables. In order to compare group means, a Shapiro-Wilk test of normality was carried out, following which an independent-samples t-test was conducted. Fisher's exact test was used to compare groups differing in the number of deliveries and urine incontinence (i.e., presence vs. absence). The significance level was specified as .05. Additionally, the effect size (r) was calculated to compare effect sizes across survey items. An effect size that was between 0 and a value less than 0.1 was indicative of “no effect”; an effect size between 0.1 and a value less than 0.3 was described as “small”; an effect size between 0.3 and a value less than 0.5 was described as “medium”; and an effect size that was higher than 0.5 was described as “large.”

Results indicated that the mean step count of the sample was 6,820 ± 2419 steps (N = 20). The number of participants in the high step count group was 8 (mean age = 64.3 ± 11.1 years, mean step count = 8927 ± 2334 steps) whereas the number of participants in the low step count group was 12 (mean age = 69.8 ± 9.7 years, mean step count = 5416 ± 1120 steps). Further, no significant differences in basic attributes emerged between these two groups (Table 1).
Exercise (i.e., amount of physical activity = intensity of physical activity × time) was found to be significantly lower in the low step count group, when compared to the high step count group (p = 0.00 r = 0.64). The low step count group scored higher than the high step count group on the composite ICIQ-UI SF score, although the difference was not statistically significant (p = 0.09, r = 0.39). Scores on the TUG test were marginally higher for the low step count group, when compared to the high step count group, although the difference was not statistically significant (p = 0.06, r = 0.43). This indicates that the two groups differed in overall physical abilities. (Table 2)

The average number of steps for Japanese women is 5867.The study sample’s mean step count was found to exceed that of Japanese women’s mean step count. Therefore, it can be inferred that women with urinary incontinence tend to be more careful about their health than the average woman. With regard to the finding that the low step count group engaged in lower levels of exercise (i.e., intensity of physical activity × time) than the high step count group, the differential contributions of the intensity of physical activity and time invested in physical activity cannot be determined. However, given that no significant difference in METs emerged between the two groups, this finding may be attributable to the time invested in physical activity. Although no significant difference in the composite ICIQ-UI SF score of the two groups emerged, the low step count group did obtain a higher score than the high step count group. This indicates that the former group may have greater concerns about the effects of urinary incontinence on everyday functioning. Together, the findings suggest that urinary incontinence among participants in the low step count group affects their daily life, by making it difficult for them to sustain physical activity across long periods of time.
A significant limitation of this study pertains to sampling bias because the sample  consisted of participants who were presumably interested in urinary incontinence. Future studies can use larger samples and qualitative methodologies in order to obtain an in-depth understanding of urinary incontinence and its implications for different types of physical activities.

The results of this study suggest that urinary incontinence makes it difficult for middle-aged and older women to sustain physical activity over long periods, thereby affecting daily life. Therefore, in order to prevent or manage pelvic floor dysfunction, it is important to regularly engage in exercises such as walking.