For decades the advice during cancer treatment was rest. The evidence now points the other way: staying active through treatment reduces fatigue, protects muscle, improves mood and sleep, helps glucose control, and in several cancer types is associated with better outcomes.
This is not about training hard. It is about not disappearing.
Exercise is the most consistently evidence-supported complementary intervention in oncology. Cancer-related fatigue responds better to movement than to rest, which is the opposite of what fatigue tells you to do.
What the guidance actually says
Major oncology and exercise-medicine bodies converge on roughly:
- 150 minutes of moderate aerobic activity weekly, or 75 minutes vigorous
- Two resistance sessions weekly covering the major muscle groups
- Flexibility and balance work, particularly with neuropathy or after surgery
- Anything is better than nothing, benefit starts well below the target
Scale it to the week you are actually in. A ten-minute walk on a chemotherapy week counts.
Why resistance training matters most
Treatment drives muscle loss through inactivity, poor intake, inflammation and steroids. Muscle loss predicts worse chemotherapy tolerance, more dose reductions and slower recovery. It also worsens insulin resistance, muscle is where most glucose disposal happens, which is why this section matters doubly if you have diabetes.
Two sessions a week of basic resistance work, sit-to-stands, wall push-ups, resistance bands, light dumbbells, carrying groceries deliberately, protects the thing that protects you.
Scaling to how you feel
Good day. Full session: 20–30 minutes of walking or cycling plus a resistance circuit.
Average day. Half of it. Walk 15 minutes, do one round of bands.
Bad day. Five minutes of gentle movement, breathing work, ankle pumps, standing up once an hour. This still counts and still protects function.
Infusion day. Short walks between and after. Movement helps nausea and sleep more than lying still does.
Very low counts, fever, uncontrolled pain, severe anaemia, new dizziness. Stop and check with your team before continuing.
Situations that need specific advice
- After breast surgery or lymph node removal: progressive resistance training is now considered safe and protective for lymphoedema risk, but start with a physiotherapist who knows oncology.
- Bone metastases: avoid high-impact and heavy axial loading; you need an individualised plan, not a generic one.
- Peripheral neuropathy: prioritise balance work and choose stable equipment, a recumbent bike over a treadmill, supported movements over free-standing ones.
- Stoma, port or recent surgery: ask specifically about lifting limits and timelines rather than guessing.
- Cardiotoxic regimens (anthracyclines, trastuzumab): aerobic training is generally encouraged and may be protective, with monitoring.
Doing it with someone
Adherence roughly doubles with a partner. Walk with a family member, join a cancer-specific exercise programme, or use a video call while you both do the same ten minutes. Many hospitals and cancer charities run free supervised programmes, ask for a referral to exercise oncology or cancer rehabilitation. It exists and most people are never told.
Tracking that helps
Keep it light: minutes moved, how you felt (1–5), and one strength marker, how many sit-to-stands in thirty seconds, or how far you walked before needing to stop. Retest monthly. Seeing function hold steady through treatment is genuinely motivating, and it gives your team something objective to work with.
If you use GLUCORAiQ, logging activity alongside glucose also makes the steroid-week pattern visible, and progress photos plus the strength marker give you a before-and-after that a scale cannot show.
Frequently asked questions
I am exhausted. Will exercise make it worse?
Cancer-related fatigue is one of the few kinds of tiredness that generally improves with gentle activity and worsens with prolonged rest. Start with five minutes and judge by how you feel an hour later, not during.
Is it safe during chemotherapy?
For most people, yes, with adjustments. Clear it with your team, avoid gyms when counts are very low, and stop for fever, chest pain, new dizziness or unusual shortness of breath.
Does it help my blood sugar too?
Yes. Muscle contraction moves glucose into cells independently of insulin, which is particularly helpful on steroid days. Watch for lows if you use insulin or sulfonylureas.
What if I have never exercised?
Then walking and sit-to-stands are your programme. There is no prerequisite, and the biggest proportional gains in these studies come from people who started at zero.
Educational content only, not medical advice. Clear any exercise programme with your oncology team, especially with bone metastases, cardiac history or recent surgery.