<qa>  What is the primary hypothesis that individuals randomized to either phone or print conditions will exhibit significantly higherThe objective of this study is to determine the differential effect of intervention delivery channel phone versus print versus wait list control on physical activity adoption and maintenance in previously sedentary adults. Both delivery channels have been found to be effective, but telephone-based interventions require more commitment on the part of the subjects and are more labor intensive than print-based interventions. Thus, we will conduct a randomized controlled clinical trial comparing three groups: 1 telephone-based motivationally-tailored individualized feedback; 2 print-based, motivationally-tailored individualized feedback; 3 minimal contact waiting list control condition receive intervention after 12 months as controls. Two hundred and twenty-eight healthy, sedentary women and men ages 18-65 will be randomly assigned to one of the two interventions or the waiting-list control condition. Our primary hypothesis is that individuals randomized to either phone or print conditions will exhibit significantly higher levels of physical activity participation at 6 and 12 months than individuals in the waiting list control condition. And, in addition, that subjects randomized to the telephone condition will exhibit significantly higher levels of physical activity participation at 6 and 12 months than those in the print condition. 