Who this is for
Exercise after colon cancer treatment is becoming an important discussion for patients who have completed surgery and chemotherapy.
People with stage II or stage III colon cancer who have completed surgery and chemotherapy and are wondering what else they can do to reduce the risk of recurrence. This information may be particularly relevant for patients seeking a colon cancer second opinion in Melbourne, Australia, Sri Lanka, the Maldives, Indonesia, or the Philippines.
A 52-year-old woman recently asked me a question that many patients ask after finishing chemotherapy.
“Doctor, is there anything else I can do?”
She had undergone surgery.
Chemotherapy was now complete.
Every appointment had been attended, and every recommendation had been followed.
What she wanted to know was whether anything under her own control could make a meaningful difference.
Until recently, the answer was uncertain.
Today, we have stronger evidence.
Exercise after colon cancer treatment: What did the CHALLENGE trial show?
The CHALLENGE trial was a large international study published in the New England Journal of Medicine.
It included 889 patients with high-risk stage II or stage III colon cancer.
All patients had already completed the main standard treatments:
- Surgery
- Chemotherapy after surgery
The study then asked a very practical question:
Could a structured exercise program help reduce the chance of colon cancer coming back?
Patients were divided into two groups.
Standard Health Education Group
One group received standard health education materials.
These materials encouraged healthy lifestyle behaviours.
Structured Exercise Group
The other group took part in a structured exercise program for 3 years.
They were supported by trained exercise consultants.
During the first year, patients had regular exercise consultations. After that, they continued with less frequent support.
The exercise target was approximately 10 MET-hours per week.
In simple terms, for many patients, this was similar to 45–60 minutes of brisk walking around 3–4 times per week, depending on exercise intensity.
However, this did not mean everyone had to do the same activity.
Many patients used brisk walking, cycling, swimming, jogging or similar aerobic exercise.
The important point was that the exercise was structured, supported and built up gradually.
Key results
- More Patients Remained Cancer-Free
After 5 years, 80.3% of patients in the exercise group were alive without the cancer coming back, compared with 73.9% in the health education group.
In simple terms, more patients remained well and cancer-free when they followed the structured exercise program.
- The Chance of Cancer Coming Back Was Lower
Patients in the exercise group had a 28% lower risk of the cancer returning, a new cancer developing, or death.
This means exercise was linked with better cancer control after treatment.
- More Patients Were Alive Years Later
After 8 years, 90.3% of patients in the exercise group were alive, compared with 83.2% in the health education group.
This suggests the benefit of exercise may last beyond the first few years after treatment.
What do these results mean?
This study does not mean that exercise replaces surgery or chemotherapy.
Importantly, every patient in the CHALLENGE trial had already received standard treatment before entering the study. They had surgery, and they had completed chemotherapy.
Instead, the message is that exercise may add something meaningful after standard treatment is finished.
What surprised many oncologists was the size of the benefit. This was not a small or trivial finding. In fact, the improvement seen with structured exercise was similar to the type of benefit oncologists would usually take very seriously if it came from several months of additional chemotherapy.
If a new cancer drug produced this kind of result, it would attract a lot of attention.
However, in this study, the treatment was not a new tablet or infusion. It was a structured, supported exercise program.
For patients, this is an empowering message.
It does not mean they need to become athletes. Rather, it means that regular, moderate exercise after colon cancer treatment may help reduce the chance of the cancer returning and may improve long-term health.
For many patients, this could be something as simple as brisk walking, cycling, swimming, or similar activity, built up safely and consistently over time.
For patients who are still deciding whether chemotherapy is needed after colon cancer surgery, our article on ctDNA testing after colon cancer surgery may also be helpful.
Summary
For many years, exercise after colon cancer treatment was seen as good general health advice.
The CHALLENGE trial changed that conversation.
It showed that a structured exercise program after surgery and chemotherapy helped more patients remain alive and free from cancer recurrence.
The study also suggested that regular exercise may improve long-term survival.
For patients, the message is encouraging.
Exercise does not replace surgery, chemotherapy or follow-up care. However, when started safely and continued consistently, it may become an important part of recovery and survivorship after colon cancer treatment.
Key takeaways
- Exercise after colon cancer treatment may matter more than we once thought
Structured exercise after surgery and chemotherapy may help reduce the chance of colon cancer returning. - Exercise does not replace standard cancer treatment
The patients in the CHALLENGE trial had already completed surgery and chemotherapy before starting the exercise program. - Patients do not need to become athletes
For many people, regular moderate exercise such as brisk walking, cycling or swimming may be a realistic starting point. - Exercise should be started safely and built up gradually
The right plan depends on recovery from surgery, chemotherapy side effects, fitness level and general health.
Key evidence
- Courneya KS, Vardy JL, O’Callaghan CJ, et al. Structured exercise after adjuvant chemotherapy for colon cancer. N Engl J Med. 2025;393(1):13-25. doi:10.1056/NEJMoa2502760
- Pentheroudakis G, Argilés G, Arnold D, Smyth E, Ducreux M. ESMO Clinical Practice Guideline Express Update on the adoption of physical exercise in patients with localised colon cancer. ESMO Open. 2026;11(2):106019. doi:10.1016/j.esmoop.2025.106019
- Cormie P, Atkinson M, Bucci L, et al. Clinical Oncology Society of Australia position statement on exercise in cancer care. Med J Aust. 2018;209(4):184-187. doi:10.5694/mja18.00199
Frequently asked questions (FAQs)
- Can exercise replace chemotherapy?
No.
The patients in the CHALLENGE trial had already completed surgery and chemotherapy. Exercise was used after standard treatment, not instead of it.
- Do I need to join a gym?
No.
Many patients can start with walking. Brisk walking, cycling, swimming or similar activities may all be suitable, depending on your fitness and medical condition.
- How much exercise are we talking about?
The study aimed for approximately 10 MET-hours of recreational exercise per week. For many patients, this is roughly similar to 45–60 minutes of brisk walking around 3–4 times per week, depending on intensity.
- Is walking enough?
For many patients, yes.
The most important point is regular, sustained activity. It does not need to be extreme exercise.
- When should I start exercising after colon cancer treatment?
This depends on your recovery, surgery, chemotherapy side effects and general health. It is best to ask your treating team when it is safe to begin.
- What if I feel too tired after chemotherapy?
Start slowly.
Even short walks can be a useful beginning. The goal is not to push too hard, but to gradually rebuild strength and confidence.
Dr Dilanka De Silva
MBBS, MRCP(UK), MRCP(UK SCE Oncology), FRACP, PhD
Medical Oncologist & Cancer Genetics Physician
Memorial Sloan Kettering Cancer Center Fellow (New York, USA)