Abstract
BACKGROUND: More than half (55%) of Latina women do not meet aerobic physical activity (PA) guidelines, and frequently cite time, childcare, and transportation as barriers to PA. In addition to linguistic adaptations for this population, successful PA interventions for Latina women addressed these barriers through remote intervention delivery approaches (eg, mail, phone, or web delivery). OBJECTIVE: We aimed to evaluate 6-month outcomes of a randomized trial comparing a Spanish-language, individually tailored, web-delivered PA intervention (original) to an enhanced version with text messages and additional features (enhanced). Further, we evaluated if increases in PA at 6 months were moderated by baseline activity status. METHODS: In total, 195 Latina women aged 18-65 years participated in a trial comparing the efficacy of the enhanced versus original interventions at initiating PA behavior change. We examined minutes per week of accelerometer-measured PA in the enhanced versus original arms, and the proportion of each arm meeting aerobic PA guidelines (150 min/wk at 6 mo). For moderator analyses, participants were classified as inactive (0 min/wk) or low active (1-90 min/wk) at baseline, measured via the 7 Day Physical Activity Recall interview. RESULTS: PA increased from 19.7 (SD 47.9) minutes per week at baseline to 46.9 (SD 66.2) minutes per week at 6 months in the enhanced arm versus 20.6 (SD 42.7) minutes per week to 42.9 (SD 78.2) minutes per week in the original arm (P=.78). Overall, 30% (31/103) of the enhanced group met aerobic PA guidelines at 6 months, compared to 21% (19/92) of the original group (odds ratio [OR] 1.75, 95% CI 0.87-3.55). Baseline PA (inactive vs low active) moderated treatment effects on PA. For inactive participants, there were no group differences at 6 months (b=7.1; SE 22.8; P=.75), while low-active participants increased more in enhanced than original (b=72.5; SE 27.9; P=.01). For low-active participants, 45% (46/103) of the enhanced group met PA guidelines at 6 months, versus 20% (18/92) of the original arm (OR 3.29, 95% CI 1.05-11.31). For inactive participants, there were no group differences (25/103, 24% vs n=19/92, 21% for enhanced vs original, respectively; OR 1.28, 95% CI 0.54-3.06). CONCLUSIONS: Intervention effects were conditional on baseline PA. For low-active Latina women, the enhanced intervention was more effective at increasing PA. Additional tailored intervention enhancements may be necessary to increase PA for inactive Latina women. TRIAL REGISTRATION: ClinicalTrials.gov NCT03491592; https://www.clinicaltrials.gov/study/NCT03491592. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s13063-022-06575-4.