Roles and molecular mechanisms of physical exercise in cancer prevention and treatment

•Physical exercise reduces cancer risks, enhances quality of life, and improves the prognoses of patients with cancer.•Physical exercise should be considered an important intervention to prevent and treat cancer and its complications.•Sensitivity to physical exercise varies in different cancers; we provide evidence for the exercise type and strength in various cancers and in differing stages.•Inhibiting cancer cell proliferation and inducing apoptosis and regulating metabolism and the immune environment are the main mechanisms of the benefits of physical exercise in cancer prevention and treatment. Exercise can enhance motivation to change lifestyle behaviors, improve aerobic fitness, improve physical function, control fatigue, and enhance quality of life. Studies have demonstrated the benefits to be gained from physical exercise, highlighting the importance of popularizing the concept of physical exercise for individuals and making professional exercise-treatment programs available to patients with cancer. However, the correlation between physical exercise and carcinogenesis is easily overlooked, and exercise interventions are not routinely provided to patients with cancer, especially those with advanced cancer. In this article, we present a literature review of the effects of exercise on cancer development and progression and give recent evidence for the type of exercise best suited for different types of cancer and in different disease stages. Moreover, the molecular mechanisms about regulating metabolism and systemic immune function in cancer are summarized and discussed. In conclusion, physical exercise should be considered as an important intervention for preventing and treating cancer and its complications. [Display omitted]