Short-Term Effects of an mHealth Intervention on Healthy Behaviors and Cardiometabolic Health in Sedentary Employees: Quasi-Experimental Study

BACKGROUND: Sedentary employees face increased chronic health risks due to physical inactivity, immobility, and unhealthy eating behavior. Although mobile health (mHealth) interventions have shown promise in improving lifestyle behaviors, their effectiveness in occupational settings remains underexplored. Building on our previous workplace interventions, this study developed and evaluated a mobile-enabled web app-SIMPLE HEALTH-integrating activity tracking, healthy eating, and behavioral support for sedentary employees. OBJECTIVE: This study evaluated the short-term effects of a 12-week mHealth intervention on physical activity, sedentary behavior, dietary habits, and cardiometabolic health indicators among sedentary employees in Taiwan. METHODS: A 2-arm quasi-experimental study was conducted at two aerospace industrial workplaces. A total of 101 sedentary employees (mean age 46.9, SD 12.2 years; 51.5% female) were allocated by coin toss to either the intervention group (n=50) or control group (n=51). The intervention group participated in the SIMPLE HEALTH program, an mHealth intervention grounded in Social Cognitive Theory and the Ecological Model, consisting of eight components: activity tracking, goal setting, behavior logging, reminders, personalized advice, educational and motivational e-booklets, and individual and team challenges. The control group received six print educational booklets. Cardiometabolic biomarkers, objectively measured physical activity (Fitbit Charge 3), occupational sitting (occupational sitting and physical activity questionnaire), and dietary behavior (3-day photographic food records and the healthy eating behavior inventory) were assessed at baseline and 12 weeks. Data were analyzed using generalized estimating equations following the intention-to-treat principle. RESULTS: At 12 weeks, the intervention group showed significant improvements in step counts (B 1227.13, 95% CI 2.90 to 2451.36; P=.049), moderate physical activity (B 0.17, 95% CI 0.01 to 0.33; P=.04), and dietary behaviors-reduced intake of calories (B -144.59, 95% CI -276.57 to -12.60), carbohydrates (B -19.88, 95% CI -37.99 to -1.78), fats (B -6.99, 95% CI -13.69 to -0.29), and grains (B -1.46, 95% CI -2.43 to -0.50), and increased vegetable intake (B 0.47, 95% CI 0.06 to 0.88), compared to the control group (all P