Dr. Fei Xu is an epidemiologist atNanjing municipal Center of Disease Control &Prevention and an adjunct professor of NanjingMedical University.His current research interests include: physical activity and its associated influence factors, therelationship between physical activity and obesity/diabetes, built environment and humanhealth,population-based physical activity promotion/intervention and obesity/diabetes prevention, health education and health literacy promotion.Dr. Xu worked at The University of Queensland School of Population Health and FlindersUniversity Medical School in Australia, and John's Hopkins Bloomberg School of Public Healthin USA. He has led several large-scale epidemiological community-based studies, and publishedmore than 150 papers in Chinese and 50 in English over the past decade.