Background
Media
Most people now know that physical activity is vital for health. Over the past few decades, if one has seen a physician, read the news, or obtained brochures from their health insurance or flyers from a local gym, they are likely aware of this fact. Indeed, we are constantly reminded of the need to engage in adequate physical activity. Media and public health messages frequently assert that “Regular physical activity is one of the most important things people can do to improve their health” [However, to many of us, it is less clear how exactly to engage in an “adequate” amount of physical activity and whether we are doing enough. Guidelines on the amounts and types of physical activity needed to promote one’s health have shifted over time [A large body of research has explored how to promote higher levels of physical activity, for example, by leveraging wearable activity trackers and smartphone apps [