Walking to meet health guidelines: The effect of prompting frequency and prompt structure.

Abstract
This study assessed the effects of frequency of prompting (phone calls once a week versus once every 3 weeks) and structure of prompting (high versus low structure) in 135 participants (132 women and 3 men) in a walking program designed to meet the American College of Sports Medicine's cardiovascular exercise goals. Survival analysis using 6 months of data points and using the criteria of walking at least 20 min a day for at least 3 times per week indicated an effect for more frequent versus less frequent prompting (46% and 13%) but not for high- versus low-structure prompting (30% and 31%). The results suggested the efficacy of frequent prompting delivered in inexpensive ways as a means to increase exercise adherence and the further parametric study of other basic behavior change strategies.