Purpose: The purpose of this study was to evaluate a 12-week workplace e-mail intervention designed to promote physical activity and nutrition behavior.
Design: A pre- and post-test design was conducted to compare the effects of e-mail messages between intervention and control groups.
Setting: Five large workplaces in Alberta, Canada.
Subjects: Employees with access to a personal e-mail address (N = 2121) were randomly assigned to an intervention (n = 1566) or a control group (n = 555).
Intervention: Physical activity and nutrition messages were based on social-cognitive theories. The intervention group received one physical activity and one parallel nutrition message per week for 12 weeks. The control group received no weekly messages.
Measures: Each participant completed self-report measures of physical activity and nutrition related to knowledge, attitudes, and behaviors 1 week before (time 1) and 1 week after (time 2) the intervention.
Results: The intervention group was more efficacious at time 2 on measures of self-efficacy, pros, cons, intentions, and behavior related to physical activity. This group also reported more favorable changes in practicing healthy eating, balancing food intake with activity level, cooking meals with techniques to reduce fat, and avoiding eating high-fat foods. Effect sizes for all significant differences were small.
Conclusion: E-mail is a promising mode of delivery for promoting physical activity and nutrition in the workplace. Further theoretically driven studies are needed.