Background: Sedentary habits may increase the noncommunicable disease risk factors, and few teens get enough physical activity. Therefore, the current study aimed to examine the effects of a web-based intervention on the promotion of physical activity among adolescents using the transtheoretical model (TTM).
Methods And Materials: A quasi-experimental study was conducted on 278 high school students who were randomly allocated into one of the three groups: two web-based intervention groups.