Purpose: Develop and test a Web site to encourage physical activity (PA) by sedentary workers.
Design: Randomized control design with 30-day follow-up.
Setting: Large manufacturing plant.
Subjects: Included 221 workers; average body mass index was 29.5.
Intervention: Get Moving was a repeat-visit Web site providing information and support to develop a personalized PA plan.
Measures: Self-reported: PA, depression, anxiety, stage of change, attitudes, knowledge, self-efficacy, intention, perceived barriers to PA, and motivation.
Analysis: Multivariate analysis of covariance and univariate analysis of covariance models were used to compare the two study conditions on posttest outcomes, controlling for baseline levels.
Results: Compared with the control group, the treatment group showed significant improvement. The multivariate test was significant (p < .001), with a large effect size (η(2) = .42). The treatment group differed significantly from the control participants on 11 outcomes (p < .005), with large effect sizes for PA status, min/d, and knowledge, attitudes, and behavioral intention. Medium effect sizes were measured for perceived barriers, depressive symptoms, motivation, and self-efficacy. Multiple visits resulted in significantly improved PA, motivation, self-efficacy, and intention, compared with one-time visits.
Conclusions: The Get Moving Web site had positive effects and was well received. Interventions Web site have potential to increase the PA of sedentary individuals in worksites and elsewhere, but more research is needed into mediators of Web-based interventions.