Six-month follow-up and participant use and satisfaction of an electronic mail intervention promoting physical activity and nutrition.

PURPOSE To evaluate the effects of a 12-week e-mail intervention promoting physical activity and nutrition, and to describe participant use and satisfaction feedback. DESIGN A longitudinal, randomized trial. SETTING Five large workplaces in Alberta, Canada. PARTICIPANTS One thousand forty-three participants completed all three assessments, and 1263 participants in the experimental group provided use and satisfaction feedback after receiving the 12-week intervention. INTERVENTION Paired physical activity and nutrition messages were e-mailed weekly to the experimental group. The control group received all messages in bulk (i.e., within a single e-mail message) at the conclusion of the intervention. MEASURES Self-report measures of knowledge, cognitions, and behaviors related to physical activity and nutrition were used. Satisfaction with e-mail messages was assessed at Time 2. ANALYSIS Planned contrasts compared the experimental group measures at Time 3 with those reported at Time 2 and with control group measures reported at Time 3. Control group measures at Time 3 were also compared with control group measures at Time 2. RESULTS The small intervention effects previously reported between Time 1 and Time 2 were maintained at Time 3. Providing the e-mail messages in bulk also had a significant positive effect on many of the physical activity and nutrition variables. CONCLUSIONS E-mail offers a promising medium for promoting health-enhancing knowledge, attitudes, and behaviors. Additional research is needed to determine optimal message dose and content.