Exercise after cancer: how much, how to start, what to avoid

When you are exhausted, being told to exercise can sound absurd or even unkind. But the evidence here is unusually consistent: graded, sustainable activity improves fatigue rather than worsening it, and it does so more reliably than any medication studied for the purpose. The skill is starting far below what you think you should be able to do, and increasing slowly enough that you never have to stop.

The international multidisciplinary roundtable on exercise for cancer survivors concluded that specific doses of exercise improve fatigue, anxiety, depression, physical function and health-related quality of life. World Health Organization physical activity guidance includes people living with chronic conditions and cancer.

• Aerobic: aim towards 150 minutes a week of moderate activity — brisk enough that talking is possible but singing is not — or 75 minutes of vigorous activity.
• Resistance: two sessions a week working the major muscle groups. This is the part most often skipped and the part that restores function fastest.
• Balance and flexibility: useful for everyone, and important if you have neuropathy or have lost confidence.
• Reduce sitting: breaking up long sitting matters independently of formal exercise.
• Something is better than nothing: benefits start well below the target, and the guidance says so explicitly.

1. Week one: walk five to ten minutes, most days. Same time each day if possible.
2. Weeks two to four: add one to two minutes per walk. Add sit-to-stands from a chair — one set of five, twice a week.
3. Month two: build one walk towards twenty minutes. Add wall push-ups and a step-up. Two strength sessions a week.
4. Month three: aim for thirty minutes on most days, with some of it brisk. Increase strength work to two or three sets.
5. Beyond: increase by around ten per cent a week, and when a week goes badly return to the previous level rather than to zero.

Most people can and should exercise, including during treatment. Get individual advice before starting, or adapt, in these situations:

• Bone metastases or significant bone thinning — impact and heavy loading may need modification, but activity is still recommended.
• Significant anaemia or very low platelets — usually a temporary restriction.
• Active infection or fever — wait.
• A stoma, hernia, or unhealed surgical wound — get advice on abdominal loading and swimming.
• Central lines and PICC lines — advice on swimming and upper-body loading.
• Heart or lung conditions, or new breathlessness, chest pain, palpitations or dizziness on exertion — get assessed first.
• Severe neuropathy or unsteadiness — favour supported exercise, and see neuropathy.
• Lymphoedema or risk of it — resistance training is now recommended rather than avoided; progress gradually and get advice on compression.

• Ask about cancer rehabilitation or prehabilitation programmes — many hospitals and cancer support centres run supervised classes free of charge.
• Physiotherapy is appropriate for surgical recovery, shoulder problems after breast or head and neck surgery, pelvic floor issues and balance.
• Cancer-specific exercise qualifications exist; if you use a gym or trainer, ask whether they have one.
• Group programmes have an additional benefit that is not about muscle: being around people who understand.