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Assessment of Physical Activity Intensity with Accelerometers and Oxygen Consumption
Published on: June 20, 2025
Physical activity outcomes from a randomized trial of a theory- and technology-enhanced intervention for Latinas: the
Bess H Marcus1, Shira Dunsiger2, Dorothy Pekmezi3
1Department of Behavioral and Social Sciences, Center for Health Promotion and Health Equity, School of Public Health, Brown University, 121 South Main Street, Providence, RI, 02903, USA. bess_marcus@brown.edu.
Abstract:
Latina women report disproportionately high and increasing prevalence of chronic health conditions (obesity, diabetes) related to low physical activity levels. Efforts to date at addressing high rates of physical inactivity in this at-risk population have shown modest success. The original Seamos Saludables (sample size N = 266) was a culturally and linguistically adapted, print-based physical activity intervention that showed significant increases in moderate to vigorous physical activity (MVPA) from baseline to 6 months. However, only 11% of intervention participants reached the national PA guidelines of ≥ 150 min/week of aerobic MVPA. The current study tests the original Seamos Saludables intervention (Original Intervention) against an enhanced iteration Seamos Activas II (Enhanced Intervention). Study aims and intervention refinements focus on increasing the percentage of Latinas meeting national aerobic PA guidelines. For the current study (Seamos Activas II), a randomized controlled trial with (N = 199 participants) of two PA interventions (original intervention, N = 102; vs. enhanced intervention, N = 97) was conducted. Intervention refinements involved further targeting key constructs of the Social Cognitive Theory and incorporating text-message-based strategies for self-monitoring, in response to participant feedback for greater interactivity and accountability. PA assessments were conducted at baseline and 6 months. The sample was predominantly Mexican American (89%) with average age of 43.8 years (SD = 10.11) and mean BMI at baseline was 30.6 (SD = 7.56). There were significant within group increases in MVPA from baseline to 6 months (p < .05) in both Original and Enhanced Intervention arms. However, quantile regression models did not indicate significant differences in 6-month outcomes between conditions controlling for baseline, p = 0.73. There were significant differences between conditions with respect to meeting national guidelines for aerobic MVPA at 6 months, with 57% of Enhanced Intervention participants meeting guidelines compared to 44% of Original Intervention participants, OR = 1.66, 95% CI: 1.09 -2.89. Models suggest trends favoring the enhanced condition for improvements in biomarkers over 6 months. Findings indicate that the intervention enhancements likely helped more Latinas achieve nationally recommended, health enhancing PA levels than the original intervention and showed promise for improving physiological response to exercise.Trial Registration ClinicalTrials.Gov; NCT02630953. Registered 14 December 2015. https://clinicaltrials.gov/ct2/show/NCT02630953 .
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