David J. Stensel is Professor of Exercise Metabolism and Associate Dean for Research in the School of Sport, Exercise and Health Sciences at Loughborough University, UK. He is also the Lifestyle Theme Lead for the National Institute for Health Research (NIHR) Leicester Biomedical Research Centre and Associate Editor for the International Journal of Obesity.

Adrianne E. Hardman is Emeritus Professor of Human Exercise Metabolism at Loughborough University, UK. She has over 30 years' experience in university teaching and research, has published widely, given invited lectures in many countries, and has contributed to the development of guidelines on physical activity in the UK and in North America.

Jason M.R. Gill is Professor of Cardiometabolic Health at the University of Glasgow, UK. He leads an active multi-disciplinary research group investigating the effects of physical activity and wider lifestyle on the prevention and management of vascular and metabolic diseases. He is also Director of his university's MSc in Sport and Exercise Science and Medicine.

Part I: Assessing the evidence, 1. Introduction, 2. The nature of the evidence, 3. Physical activity and mortality, Part II: Influence of physical activity on the risk of disease, 4. Cardiovascular disease, 5. Type 2 diabetes, 6. Obesity, 7. Cardio-metabolic risk factors, 8. Cancer, 9. Skeletal health, 10. Mental health, Part III: Physical activity in youth and old age, 11. Child and adolescent health, 12. Ageing, Part IV: Physical activity - risks and opportunities, 13. Hazards, 14. Public health, Epilogue