In order to produce accurate and effective research findings, it is vital to have accurate assessment when examining the dose-response relationship between commuting exposure and health related outcomes such as cardiovascular disease and obesity. This book, therefore, focused on how to get physical activity into everyday life through active commuting, in order to prevent non-communicable diseases and improve public health. This book draws attention to some of the methodological complexities in the field of physical activity and public health research and critically examining study designs, methods, and analysis in health research. It should be useful for graduate students studying public health, physical activity and health-risk behaviour. In addition, it will also be of interest to academics, researchers, and practitioners who are designing theoretically based interventions. The book is based on a doctoral thesis from the University of Southern Denmark.