Physical activity change after a promotora-led intervention in low-income Mexican American women residing in South Texas

BACKGROUND: The purpose of this study was to determine physical activity (PA) preferences associated with increases in moderate-to-vigorous physical activity (MVPA) and decrease in sedentary time in Mexican American (MA) women participating in a Promotora (community health worker)-led intervention on the U.S.-Mexico border. METHODS: Enlace (‘to link’ in Spanish) was a randomized clinical trial to increase PA in low-income, MA women living in South Texas on the U.S.-Mexico border. A total of 620 participants were recruited into the study. The primary outcome was increase in moderate to vigorous physical activity (MVPA) using the Actigraph GT3X 16 Mb accelerometer. A modified version of the Community Health Activities Model Program for Seniors Physical Activity (CHAMPS) instrument was used to predict MVPA. Adjusted and unadjusted logistic regression models predicted change in MVPA by change in CHAMPS activities. ANOVA analysis determined the variance explained in change in MVPA by change in time engaged in activity. Individual effect sizes were then calculated for significant activity type change on MVPA increase. RESULTS: There were significant increases in all CHAMPS activities except aerobic machines and errand walking. An increase in leisure walking (O.R. = 2.76, p = .046), errand (O.R. = 3.53, p = .051), and brisk walking (O.R. = 4.74, p = .011), dance (O.R. = 8.22, p = .003), aerobics class (O.R. = 32.7, p = .001), and light housework (O.R. = 6.75, p = .000), were associated with a decrease in sedentary time. Significant effect sizes for MVPA were observed for jogging (1.2, p = .050), general exercise (1.6, p = .024), and other exercise not specified (2.6, p = .003). Significant effect sizes for sedentary time were detected for leisure time (.031, p = .036), errands (.017, p = .022), brisk walking (.022, p = .003), dance (.042, p = .005), and aerobics class (.013, p = .009). DISCUSSION: Participants who engaged in walking and aerobic activities through this intervention significantly increased their engagement in MVPA and decreased their sedentary time. These findings are novel, since preferences have not been examined in relation to MVPA or sedentary time in MA women. CONCLUSION: PA preferences need to be considered when aiming to promote activities that reduce sedentary time and increase PA participation among marginalized groups, such as MA women. TRIAL REGISTRATION: NCT02046343.