​​ While it is well established that the worldwide pandemic of overweight and obesity has profound effects on promoting cancer, it is now recognized that an alternative aspect of energy balance, namely physical activity and exercise have significant beneficial effects on all aspects of cancer across the spectrum from prevention through treatment and extending through survivorship. Moreover, salutary effects of physical activity and exercise extend across the age span from youth to old age and occur at all stages of cancer extending into palliative care.   While the effect of physical activity and exercise on cancer may be partially mediated through obesity control, it is clear that considerable research is required and is ongoing at both the molecular and clinical levels to better understand the associated mechanisms and to develop optimal exercise strategies.   This volume will contain chapters on the effect of exercise on biological pathways in tumor growth, state art exercise strategies and cutting edge research focused on different cancers and patient groups. It will provide an important volume in this series on energy balance and cancer and a basis for ongoing research, experimental approaches and application of evidence based practices to clinical care for patients with cancer.​