Exercise and bowel cancer: the trial that changed the advice

Exercise helps at every stage of bowel cancer. Being active lowers the risk of colon cancer. In 2025 the CHALLENGE trial showed that a coached, three-year exercise programme after chemotherapy for colon cancer meant fewer people had their cancer come back. The results also suggest more people were alive eight years on.

Exercise is one part of cancer rehabilitation in the UK, alongside eating well and support from your wider team.

Does exercise prevent bowel cancer?

No single habit prevents bowel cancer, but being active is one of the best-supported ways to lower your risk of colon cancer. The World Cancer Research Fund's Continuous Update Project, which analysed 99 studies covering more than 29 million adults, graded the evidence that physical activity protects against colon cancer as "convincing", its highest category [4]. The panel drew no conclusion for rectal cancer [4].

Activity also works indirectly: greater body fatness is a convincing cause of colorectal cancer [4], and Cancer Research UK links around 11% of UK bowel cancers to excess weight [5]. The NHS lists "stay active and exercise regularly" among the ways to reduce your risk [6].

What did the CHALLENGE trial find about exercise and colon cancer?

The CHALLENGE trial (New England Journal of Medicine, 2025) found that a three-year coached exercise programme after chemotherapy for colon cancer lowered the risk of the cancer coming back, and the results were consistent with longer survival. Five years on, 80.3% of the exercise group were alive without their cancer returning, against 73.9% given health-education materials alone [1].

The trial randomised 889 people who had had surgery and completed chemotherapy for colon cancer, at 55 centres. After a median follow-up of 7.9 years, disease-free survival was significantly longer with exercise (hazard ratio 0.72). Eight-year overall survival was 90.3% versus 83.2%, a hazard ratio for death of 0.63 [1]. The trial's main measure was disease-free survival, so the authors describe the survival result as "consistent with" longer overall survival rather than proof of it [1].

Participants had stage III or high-risk stage II colon cancer [21] and were not meeting recommended activity levels. They had weekly in-person coaching for six months, then monthly sessions in person or online. The goal was to increase exercise "by at least the equivalent of a 30-minute jog every other day", and the trial's physical activity consultants helped each person build routines that matched their abilities, preferences and normal activity levels [2].

Two caveats: musculoskeletal problems were more common with exercise (18.5% versus 11.5%) [1], and the trial studied colon cancer after chemotherapy, not every bowel cancer at every stage.

Earlier observational work pointed the same way: in a 2006 study of 832 people with stage III colon cancer, the most active had roughly half the risk of recurrence or death of the least active, though it could not prove cause and effect [3]. The evidence for other cancers is in our guides to breast cancer, prostate cancer and other cancers.

Does prehab help before bowel cancer surgery?

It can. In the PREHAB trial (JAMA Surgery, 2023), 251 adults due for bowel cancer surgery had either standard care or four weeks of supervised prehabilitation. Severe complications after surgery fell from 29.7% to 17.1% [13].

The programme combined high-intensity exercise three times a week with a nutritional intervention, psychological support and a smoking cessation programme. Medical complications were also less common (15.4% versus 27.3%) [13]. If you are waiting for surgery, ask your colorectal nurse specialist whether your hospital runs a prehab service. Our prehabilitation guide covers what prehab involves and what the NHS offers.

Can you exercise with colon cancer?

Yes, in almost every case, and the guidance is to avoid inactivity rather than to rest. Macmillan says "being active before, during and after cancer treatment is safe", but advises talking to your cancer doctor, specialist nurse or GP before you start [10].

The 2019 American College of Sports Medicine roundtable agreed that exercise is generally safe for cancer survivors, that every survivor should "avoid inactivity", and that exercise improves fatigue, anxiety, depressive symptoms, physical functioning and quality of life [12].

During chemotherapy the right amount varies week by week: "If you're feeling very tired, don't push yourself to exercise" [7]. Our guides to exercise during chemotherapy and cancer-related fatigue cover this in more detail.

When can you exercise after bowel cancer surgery?

You can start gently once your healthcare team agrees, then build up a little each day. Bowel Cancer UK suggests beginning with a walk around the house, then a short walk outside, working towards 30 minutes of moderate exercise, such as fast walking, on at least five days a week [7].

Check with your healthcare team or physiotherapist before starting any vigorous activity [7]. Whether you had a hemicolectomy, an anterior resection or another operation [8], ask before lifting, running or core work: how soon, and how much, depends on your operation and how you are healing. Once treatment is over, our guide to exercise after cancer treatment covers rebuilding your fitness.

Can you exercise with a stoma?

Yes. A stoma is not a reason to stop exercising, but get the agreement of your doctor or stoma care nurse first and build up slowly. Colostomy UK suggests starting with activities such as walking, swimming or cycling [9].

The main concern with exercise is a parastomal hernia: a bulge or swelling around or under the stoma. Colostomy UK reports that it affects up to 70% of people with a stoma, and that strain from lifting or strenuous gardening is one of the contributing factors [9].

Exercise helps here. In Colostomy UK's words: "Strengthening your core muscles, strengthens the abdominal wall which in turn reduces the risk of a hernia forming, or can improve comfort if you already have a hernia" [9]. Its advice:

• "Allow your body to recover after surgery and introduce exercise slowly – do not push yourself too hard too soon" [9]
• Get agreement from your doctor or stoma care nurse before you return to sport [9]
• Wear support garments [9]

Who can help with eating and drinking with a stoma?

Your stoma care specialist nurse is the first person to ask. Bowel Cancer UK says they should give you information on diet when you leave hospital, and the general advice is a balanced, healthy diet with six to eight glasses of fluid a day [14].

For the first two months after surgery your bowel will be swollen, so chew your food well [14]. Several small meals a day can make food easier to digest [15]. Tell your stoma care nurse about diarrhoea or output that stays high [15].

Your colorectal clinical nurse specialist (CNS) is "usually your first point of contact if you have any questions or concerns" [16]. A dietitian supports you if you have problems eating or drinking or need help managing your weight [16]; if you are finding it hard to put on weight, ask your GP or healthcare team to refer you [15]. Speak to your healthcare team or a dietitian before making any big changes to your diet [15]. See nutrition during cancer treatment and your cancer rehabilitation team.

What is the best exercise after colon cancer?

The best exercise after colon cancer is the one you can keep doing: regular aerobic activity, plus some strength work, built up gradually. That was the approach in CHALLENGE, where people were coached for three years on routines that suited them [1, 2].

The UK Chief Medical Officers' guidance for adults gives the targets to build towards [11]:

• Aerobic activity. At least 150 minutes of moderate activity a week, or 75 minutes of vigorous activity. In early recovery, Bowel Cancer UK's 30 minutes on five days a week is the stepping stone [7].
• Strength training. On at least two days a week. After abdominal surgery or with a stoma, introduce core work slowly [9].
• Balance and flexibility on at least two days a week if you are 65 or over.

"Any activity is better than none and more is better still" [11].

Who should you see?

For a tested, individually prescribed programme, see a clinical exercise physiologist (CEP). CEPs prescribe and deliver evidence-based exercise for long-term conditions, including cancer, and can join a voluntary register run by the Academy for Healthcare Science, accredited by the Professional Standards Authority [17, 18]. Level 4 cancer rehabilitation instructors, whom Macmillan calls cancer exercise specialists, are fitness instructors qualified to help people with cancer exercise safely [10]. Physiotherapists, a title protected by law, help you regain strength, movement and balance [16, 19]. The exercise professional tiers guide explains the differences, and cancer exercise programmes covers group options.

When to be cautious / talk to your doctor first

Talk to your oncology team before starting or changing an exercise plan [10], and get specific advice if:

• You had surgery in the last few weeks and want to lift, run or do core exercise [7]
• You have a stoma and haven't agreed an exercise plan with your doctor or stoma care nurse [9]
• You notice a new bulge or swelling around your stoma [9]
• You are having chemotherapy and feel very tired; don't push through it [7]
• Your feet are numb or tingly, or your balance is poor, after chemotherapy (peripheral neuropathy): an exercise bike or swimming may suit you better than running, uneven ground or steps [20]
• Your cancer has spread to the bone, or your blood counts are low [20]
• You have a central line or PICC line: avoid swimming, because of the risk of infection, and avoid vigorous upper-body exercise, which could displace your line [20]. If you have an implanted port, ask your team what is safe. Our guide to exercise during chemotherapy has more detail
• You have another condition, such as heart disease, that changes what is safe for you

Build up gradually, and tell your team about any new pain.

Related reading

• Cancer rehabilitation in the UK
• Exercise and cancer
• Prehabilitation before cancer treatment
• Exercise after cancer treatment
• Cancer FAQs

Getting matched with a specialist

At the moment The Health Nav matches people with verified clinical exercise physiologists, in person in parts of south-west London and remotely across the UK. A CEP works alongside your colorectal team, not instead of it. If you live in London, cancer rehab in London also covers NHS and charity options near you.

Request a match with a verified clinical exercise physiologist through The Health Nav. Questions first? Email support@thehealthnav.co.uk.

This article is general information and does not replace advice from your own healthcare team.

References

1. Courneya KS, Vardy JL, O'Callaghan CJ, et al; CHALLENGE Investigators. Structured Exercise after Adjuvant Chemotherapy for Colon Cancer. N Engl J Med. 2025;393(1):13-25. https://doi.org/10.1056/NEJMoa2502760
2. Cancer Research UK. Exercise can help more people survive colon cancer. https://news.cancerresearchuk.org/2025/06/01/structured-exercise-improves-colon-cancer-survival/ (accessed 12 Oct 2026)
3. Meyerhardt JA, Heseltine D, Niedzwiecki D, et al. Impact of physical activity on cancer recurrence and survival in patients with stage III colon cancer: findings from CALGB 89803. J Clin Oncol. 2006;24(22):3535-3541. https://doi.org/10.1200/JCO.2006.06.0863
4. World Cancer Research Fund/American Institute for Cancer Research. Continuous Update Project Expert Report 2018. Diet, nutrition, physical activity and colorectal cancer. https://www.wcrf.org/wp-content/uploads/2021/02/Colorectal-cancer-report.pdf (accessed 15 Sep 2026)
5. Cancer Research UK. Risks and causes of bowel cancer. https://www.cancerresearchuk.org/about-cancer/bowel-cancer/risks-causes (accessed 15 Sep 2026)
6. NHS. Causes of bowel cancer. https://www.nhs.uk/conditions/bowel-cancer/causes/ (accessed 15 Sep 2026)
7. Bowel Cancer UK. Physical activity. https://www.bowelcanceruk.org.uk/about-bowel-cancer/living-with-and-beyond-bowel-cancer/physical-wellbeing/physical-activity/ (accessed 12 Oct 2026)
8. Bowel Cancer UK. Types of surgery. https://www.bowelcanceruk.org.uk/about-bowel-cancer/treatment/surgery/types-of-surgery/ (accessed 15 Sep 2026)
9. Colostomy UK. What is a parastomal hernia? https://www.colostomyuk.org/information/stoma-problems/parastomalhernia/ (accessed 12 Oct 2026)
10. Macmillan Cancer Support. Physical activity and cancer. https://www.macmillan.org.uk/cancer-information-and-support/treatment/preparing-for-treatment/physical-activity-and-cancer (accessed 12 Oct 2026)
11. UK Chief Medical Officers. UK Chief Medical Officers' physical activity guidelines. 2019, page updated 10 July 2026. https://www.gov.uk/government/publications/physical-activity-guidelines-uk-chief-medical-officers-report/uk-chief-medical-officers-physical-activity-guidelines (accessed 12 Oct 2026)
12. Campbell KL, Winters-Stone KM, Wiskemann J, et al. Exercise Guidelines for Cancer Survivors: Consensus Statement from International Multidisciplinary Roundtable. Med Sci Sports Exerc. 2019;51(11):2375-2390. https://doi.org/10.1249/MSS.0000000000002116
13. Molenaar CJL, Minnella EM, Coca-Martinez M, et al. Effect of multimodal prehabilitation on reducing postoperative complications and enhancing functional capacity following colorectal cancer surgery: the PREHAB randomized clinical trial. JAMA Surg. 2023;158(6):572-581. https://doi.org/10.1001/jamasurg.2023.0198
14. Bowel Cancer UK. Stomas. https://www.bowelcanceruk.org.uk/about-bowel-cancer/treatment/surgery/stomas/ (accessed 12 Oct 2026)
15. Bowel Cancer UK. Diet after treatment. https://www.bowelcanceruk.org.uk/about-bowel-cancer/living-with-and-beyond-bowel-cancer/diet-after-treatment/ (accessed 12 Oct 2026)
16. Bowel Cancer UK. The healthcare team. https://bowelcanceruk.org.uk/about-bowel-cancer/diagnosis/medical-nursing-staff (accessed 12 Oct 2026)
17. NHS Health Careers. Clinical exercise physiologist. https://www.healthcareers.nhs.uk/explore-roles/healthcare-science/roles-healthcare-science/physiological-sciences/clinical-exercise-physiologist (accessed 12 Oct 2026)
18. Academy for Healthcare Science. PSA accredited register. https://www.ahcs.ac.uk/registration/psa-accredited-register/ (accessed 12 Oct 2026)
19. Health and Care Professions Council. The professions we regulate. https://www.hcpc-uk.org/about-us/who-we-regulate/the-professions/ (accessed 12 Oct 2026)
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21. ClinicalTrials.gov. A Phase III Study of the Impact of a Physical Activity Program on Disease-Free Survival in Patients With High-Risk Stage II or Stage III Colon Cancer (CHALLENGE), NCT00819208. https://clinicaltrials.gov/study/NCT00819208 (accessed 12 Oct 2026)