This document discusses the relationship between physical activity and cancer risk and survival. It finds that higher levels of physical activity are associated with lower risks of several cancers like breast and colon cancer. The mechanisms may include lowering sex hormones and inflammation. It recommends 150-300 minutes per week of moderate activity or 75-100 minutes of vigorous activity. Physical activity is also beneficial for cancer survivors by reducing symptoms and improving quality of life. More research is still needed on topics like optimal activity levels and sedentary behavior's cancer risk impact.