October 6, 2025, 6:40 pm
TAM Desk ||
New evidence has linked physical activity with improved colon health, underscoring the vital role of exercise in cancer prevention and care.
The landmark international trial – the Challenge study – showed that structured exercise programs can dramatically improve survival rates for colon cancer survivors.
The study was unveiled at the meeting of the American Society of Clinical Oncology. Each June, cancer specialists from around the world convene in Chicago for the conference where new research is announced that pushes the boundaries of cancer treatment and this year’s conference featured a wealth of exciting discoveries.
Conducted across six countries and published in the New England Journal of Medicine, the Challenge study tracked 889 patients for several years following chemotherapy. Participants were randomly assigned to one of two groups: one received standard post-treatment care, while the other took part in a three-year coaching program that included personalized exercise plans and regular check-ins with fitness professionals.
The results were striking. Those in the exercise group experienced 28% fewer cancer recurrences and 37% fewer deaths.
In the program, people slowly built up how much they exercised, with most choosing to go on brisk 45-minute walks four times a week. Ninety per cent of the people who exercised stayed cancer free for five years, compared with just 74% of those who didn’t.
This study provides the first strong evidence that exercise not only correlates with better outcomes but directly improves survival rates in cancer patients. While earlier observational studies found a link between being active and better cancer outcomes, this first randomized controlled trial helps show causation, meaning that exercise can directly benefit the survival of cancer patients.
We don’t know yet if the same goes for other cancers like breast, prostate or lung, but it’s a big step forward.
The program’s success hinged on consistent support. Participants met with fitness coaches every two weeks at first, then monthly, which helped them stick to their routines even after treatment ended.
While minor injuries such as muscle strains were slightly more common among those who exercised (19% compared to 12% in the control group), researchers emphasied that these issues were manageable and far outweighed by the significant survival benefits.
Potential downsides to exercise?
In contrast to the encouraging findings on structured exercise, a separate study presented in Chicago has raised questions about the potential downsides of extreme endurance training.
Researchers tracking marathon runners found a higher rate of polyps (small growths in the colon that can sometimes develop into cancer) compared with the general population. This unexpected finding has sparked a fresh debate about the effect of high-intensity exercise on long-term colon health.
However, context is needed. The study did not find higher cancer rates among runners, and most of the detected polyps were low risk.
Several possible explanations have been offered: endurance athletes may simply undergo more frequent screenings, leading to increased detection, or intense exercise might temporarily raise inflammation markers. Crucially, the overall risk of cancer remains lower in active people than in those who are more sedentary, reinforcing the well-established protective benefits of regular exercise.