For decades, exercise has been loosely recommended after a broad range of cancer diagnoses because it supports an improved quality of life.

 

Both the cancer itself and cancer treatment often leaves patients dealing with fatigue, muscle loss, reduced cardiovascular fitness, pain, and decreased independence. These challenges can persist long after chemotherapy or radiation has ended.

 

A 2025 umbrella review published in the British Journal of Sports Medicine showed that exercise consistently reduces cancer-related fatigue, anxiety, depression, physical deconditioning, treatment complication while improving quality of life, physical function and overall fitness.

 

And these improved quality of life measures are not limited to early stage and lower grade diagnoses.

 

The 2024 PREFERABLE-EFFECT trial, published in Nature Medicine, focused on people living with metastatic breast cancer, a group historically underrepresented in exercise research. Participants completed a supervised program combining aerobic exercise, resistance training, balance work, and behavioural coaching over nine months.

 

The results demonstrated meaningful improvements in cancer-related fatigue, physical fitness, quality of life, pain and overall physical functioning.

 

Perhaps most importantly, the study showed that appropriately prescribed exercise is both safe and beneficial, even for individuals living with advanced cancer.

 

Exercise can and should be recommended as supportive care for almost anyone with cancer, however the science has taken a remarkable step forward in the last couple years.

 

We now know exercise isn’t simply about recovering from cancer treatment, it may actually improve cancer outcomes itself.

 

A Landmark Study Changes the Conversation

 

In 2025, researchers published the results of the CHALLENGE trial in the New England Journal of Medicine, the first large randomized controlled trial to demonstrate that a structured exercise program can reduce cancer recurrence and improve survival after treatment for colon cancer.

 

The study followed 889 patients with Stage II and III colon cancer who had completed surgery and chemotherapy. Participants were randomized to either receive standard health education or a three-year, behaviourally supported exercise program led by exercise professionals.

 

The results were striking.

 

Patients who participated in the exercise program experienced:

• 28% lower risk of cancer recurrence, developing a new primary cancer, or death
• 37% lower risk of death
• Higher disease-free survival and overall survival after nearly eight years of follow-up

 

This is a pivotal finding because randomized controlled trials are considered the highest level of clinical evidence. Previous research had shown that people who exercised tended to live longer after cancer, but it was difficult to know whether exercise itself was responsible (causation versus correlation).

 

The CHALLENGE trial provides compelling evidence that structured exercise can directly improve long-term outcomes in at least one common cancer.

 

The exact mechanisms for exercise causing better survival rates will be an area of study for decades to come.

 

However one recent hypothesis is that exercise may be able to literally starve a tumour.

 

A fascinating new study published in PNAS found that just 4 weeks of regular exercise dramatically slowed tumour growth in multiple mouse models.  Researchers found that increases in muscle glucose metabolism and reductions in tumour glucose metabolism correlated with slower tumour progression.

 

Essentially exercising muscle becomes a powerful glucose competitor pulling glucose into skeletal muscle and the heart, leaving less fuel available for tumours to grow.

 

The authors also found that exercise can reduce mTOR signalling, a major pathway that drives cell growth and is frequently overactive in cancer.

 

Yes, this is just an animal (mouse) study, so it alone does not prove anything.  However, it’s provides an interesting mechanistic framework supporting this growing body of evidence that exercise interventions may enhance future cancer prevention and treatment strategies.

 

What Does the Research Suggest Patients Should Do?

 

So what should you do, if you or a loved one is diagnosed with cancer?  While every individual requires a personalized plan, the strongest evidence supports programs that include:

 

• 150–300 minutes of moderate aerobic activity per week, such as brisk walking or cycling
• Resistance training two to three times per week to preserve and rebuild muscle
• Progressive increases based on tolerance
• Long-term consistency rather than short bursts of activity

 

For many people recovering from cancer treatment, simply beginning with regular walking and a supervised strengthening program can provide substantial benefits.  And as a mentor of mine once said, there are many roads to Rome.  How you incorporate exercise into your cancer care strategy will depend on many different factors.

 

Train for strength.  Train for cardiovascular fitness (both low intensity, longer duration sessions or higher intensity intervals can work).  Mix in some training for power, mobility and recovery if you have time as well.  You have lots of options.  And if you have questions on how to get started safely and effectively, we can help.

 

The Bottom Line

 

The message from the latest research is clear: exercise is no longer simply a way to help people recover from cancer treatment, it is becoming an important part of cancer care itself.

 

If you or someone you know has been diagnosed with cancer, talk to your healthcare team about incorporating exercise into your treatment and recovery plan.  Don’t wait for your oncologist to advise on your exercise strategy.  Your oncologist may not recommend exercise as part of your active treatment plan for various reasons; knowledge translation from academic research to clinical practice takes decades.