A comprehensive review of existing research indicates that exercise may significantly reduce the risk of cancer recurrence and improve survival rates among patients following treatment. The study analyzed data from approximately 8,500 patients across 123 studies and 21 clinical trials, revealing that those who engaged in physical activity during their aftercare were 23% less likely to experience a return of their cancer. Additionally, these individuals showed a 17% lower chance of cancer recurrence, an 18% reduced risk of death from any cause, and a 26% lower risk of dying specifically from cancer.
Michelle Mitchell, chief executive of Cancer Research UK, highlighted the broad benefits of exercise, emphasizing its potential to help cancer survivors live longer and healthier lives. She noted the importance of ensuring that patients recovering from cancer have access to appropriate support for physical activity, while acknowledging that individual circumstances and health conditions may impose limitations. Mitchell advised patients to consult their healthcare providers to determine safe and suitable forms of exercise tailored to their specific needs.
Exercise is frequently recommended to cancer patients to alleviate treatment-related fatigue and enhance mobility, though its effect on reducing tumor recurrence has been a subject of debate. Concerns remain regarding the safety of intense physical activity for patients who are weakened by surgery or chemotherapy.
Cancer recurrence occurs in an estimated 20% to 40% of patients even after undergoing treatments such as chemotherapy and tumor removal, with monitoring often involving MRI scans. Chih-Chen Tzang of National Taiwan University, one of the authors of the study, explained that aerobic exercise may contribute to systemic cardiovascular conditioning, mobilization of immune cells, and improved tumor blood flow, all of which could support better systemic control over cancer.
The cancers most frequently studied were breast, colorectal, and pancreatic. Patients participated in various forms of exercise, including aerobic activities like running and dancing, as well as strength training such as weightlifting, push-ups, and pull-ups. Researchers propose that both aerobic and resistance exercises may stimulate the immune system and enhance blood circulation within tumors, potentially increasing the efficacy of cancer treatments.
Beyond these mechanisms, exercise may also reduce circulating levels of sex hormones such as estrogen and testosterone, which can influence cancer growth. Furthermore, physical activity can increase glucose uptake by muscles, decreasing the availability of this energy source to cancer cells. The study also suggests that exercise might aid in repairing DNA damage within cells, thereby limiting mutations that could lead to more aggressive tumors.