Experts now advocate for cancer centers and insurance plans to adopt such programs as a standard care practice for colon cancer survivors.

"This is about as high a quality of evidence as you can get," said Dr. Julie Gralow, chief medical officer of the American Society of Clinical Oncology. The study, presented at ASCO's annual meeting and published in the New England Journal of Medicine, compares a cohort of patients engaged in a structured exercise regimen with those receiving only educational materials.

Conducted across Canada, Australia, the United Kingdom, Israel, and the United States, researchers monitored 889 colon cancer patients who had completed chemotherapy. Half of the participants received information promoting fitness and nutrition, while the other half engaged with a coach who offered guidance and bi-weekly meetings for the first year, followed by monthly meetings for the next two years. Coaches helped participants find ways to increase their physical activity, with many opting to walk regularly.

Remarkably, after eight years, the exercise group not only became more active but also experienced 28% fewer cancers and a 37% reduction in deaths from any cause compared to the control group. Despite some muscle strains and other minor injuries, the overall benefits far outweighed the risks.

"When we saw the results, we were just astounded," said Dr. Christopher Booth, co-author of the study and a cancer physician at Kingston Health Sciences Centre. Booth emphasized that the exercise programs can be implemented at a relatively low cost, making them an accessible and effective intervention for patients.

The study also plans to analyze blood samples to explore how exercise contributes to cancer prevention, potentially through mechanisms like improved insulin processing or enhanced immune function.

For participants like Terri Swain-Collins of Kingston, Ontario, the program has had a lasting impact. Even after the formal coaching ended, she continues to stay active, regularly walking while listening to music in the scenic countryside near her home.

Paper co-author Kerry Courneya from the University of Alberta highlighted that sustained behavior change is achievable when patients recognize the benefits, incorporate enjoyment, and have a social support structure. "Now we can say definitively exercise causes improvements in survival," Courneya stated, offering a tangible motivation for cancer patients to maintain an active lifestyle.