A Randomized Trial Examining the Relative Efficacy of Internet versus Print-Based Physical Activity Interventions

Abstract

PURPOSE: To examine the efficacy of a tailored Internet-based physical activity intervention relative to a tailored print intervention. METHODS: Sedentary participants (n=249) were randomized to one of three interventions: 1) Internet-based individually tailored feedback (Tailored Internet; TI); 2) print-based individually tailored feedback (Tailored Print; TP); or 3) physical activity websites available to the public (Standard Internet; SI). Participants completed a sub-maximal exercise treadmill test and the 7-Day Physical Activity Recall interview at baseline, six, and 12 months. The sample consisted of mostly female (82.7%) and Caucasian (81.5%) individuals with a mean age of 44.5 years and mean BMI of 29.4. RESULTS: Estimated VO2 at 85% of age predicted maximum heart rate (ml/kg/min) significantly increased from baseline to 6 and 12 months among the entire sample but no differences were found between groups (TI=25.50 to 26.14 minutes; TP: 24.79 to 26.18 minutes; SI: 24.30 to 25.70 minutes). Similarly, mean physical activity minutes per week significantly increased from baseline to 6 and 12 months but no differences were found between groups (TI= 19.75 to 161.42 minutes per week at 6 months and 125.14 minute at 12 months; TP: 20.94 to 123.12 minutes per week at 6 months and 123.20 minutes at 12 months; SI: 22.62 to 122.33 minutes per week at 6 months and 114.14 minutes at 12 months). CONCLUSIONS: Both the Internet and print interventions increased physical activity, which is important given the potential for the Internet to reach a large proportion of sedentary adults at low-cost.