Related Experiment Video
Updated: Jul 14, 2026
Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
Published on: March 7, 2019
Telephone versus print delivery of an individualized motivationally tailored physical activity intervention: Project
Bess H Marcus1, Melissa A Napolitano, Abby C King
1Miriam Hospital and Brown Medical Centers for Behavioral and Preventive Medicine, Providence, RI 02903, USA. bmarcus@lifespan.org
Objective:
Given that only 25% of Americans meet physical activity recommendations, there is a need to develop and disseminate effective, evidence-based interventions to promote physical activity. The authors tested 2 delivery channels, telephone and print, to determine whether one was more effective in promoting physical activity.
Design:
The authors randomly assigned 239 healthy, sedentary adults to (a) telephone-based individualized feedback, (b) print-based individualized feedback, or (c) contact control. Both intervention arms were guided by a motivationally tailored, theoretically driven computer expert system.
Main Outcome Measures:
Physical activity as measured by the 7-day Physical Activity Recall interview.
Results:
At 6 months, both telephone and print arms significantly increased in minutes of moderate intensity physical activity compared with control, with no differences between the intervention arms. At 12 months, print participants reported a significantly greater number of moderate intensity minutes than both telephone and control participants, who did not differ.
Conclusion:
Results suggest that both telephone and print enhance the adoption of physical activity among sedentary adults; however, print interventions may be particularly effective in maintaining physical activity in the longer term.
