Scientists in Australia have discovered that exercise may play a much bigger role in cancer recovery than previously thought. By studying women who had survived breast cancer, researchers found that just one session of resistance training or high-intensity interval training (HIIT) triggered a significant increase in protective molecules known as myokines.
The findings highlight how exercise can go far beyond fitness – providing real cancer protection, anti-inflammatory benefits, metabolic health improvements, and even support for brain function.
The Study: Exercise and Breast Cancer Survivors
The research recruited women who had successfully undergone treatment for breast cancer, a disease that affects around 2.3 million women worldwide every year according to the World Health Organization. These survivors were split into two groups:
- One performed resistance training (such as weightlifting and strength-based exercises).
- The other completed HIIT sessions (short bursts of maximum-effort exercise followed by brief recovery periods).
Both types of exercise were conducted in 45-minute sessions. Blood samples were taken immediately after exercise to measure levels of myokines – small proteins released by muscles during physical activity.
The results were striking: participants showed up to a 47 per cent increase in circulating myokines after just one workout.
What Are Myokines?
Myokines are signalling molecules released by muscle tissue, especially during contraction in physical activity. They are a subgroup of cytokines, which act as messengers in the body to regulate immune responses, cell growth, and repair.
So why are they important for cancer survivors and overall health?
Key roles of myokines include:
- Metabolic health: improving how the body processes glucose and fat, reducing the risk of diabetes and obesity.
- Anti-inflammatory effects: lowering chronic inflammation, which is linked to multiple diseases including heart disease and cancer.
- Bone formation: stimulating bone density and protecting against osteoporosis.
- Brain function: supporting neuroplasticity, memory, and mood regulation.
- Cancer protection: influencing tumour suppression and improving immune surveillance of abnormal cells.
This means that when breast cancer survivors engage in resistance training or HIIT, their muscles are not just getting stronger – they are actively producing molecules that may help prevent cancer recurrence.
Resistance Training: Building Strength and Protective Myokines
Resistance training involves exercises that use external weight or body resistance to challenge muscles. Examples include:
- Weightlifting (using dumbbells or barbells)
- Bodyweight exercises (push-ups, squats, planks)
- Resistance bands
- Machines at the gym
For breast cancer survivors, resistance training offers several unique advantages:
- Restores muscle strength lost during cancer treatment.
- Improves bone health, reducing the risk of osteoporosis caused by chemotherapy or hormone therapy.
- Stimulates myokine release, adding a layer of protection against cancer and chronic disease.
- Boosts mental health, lowering rates of anxiety and depression.
The study showed that even a single resistance training session significantly increased myokines, meaning the benefits may start almost immediately.
High-Intensity Interval Training (HIIT): Short but Powerful
HIIT is a workout style involving short bursts of maximum-intensity effort followed by periods of rest or low-intensity recovery. For example, sprinting for 30 seconds followed by walking for 60 seconds, repeated for several cycles.
HIIT is especially effective for:
- Cardiovascular health: strengthening the heart and lungs.
- Fat burning: increasing metabolism and calorie burn even after exercise.
- Time efficiency: workouts are usually shorter, ideal for busy lifestyles.
- Triggering myokine release: muscles working at maximum intensity send strong signals throughout the body.
In the study, women who performed HIIT sessions also saw up to a 47 per cent increase in circulating myokines. This shows that both strength-based and cardiovascular-focused exercise can produce similar biochemical benefits.
Why Exercise Matters for Breast Cancer Survivors
Breast cancer survivors often face long-term health challenges after treatment. Fatigue, weight gain, reduced bone density, and increased risk of recurrence are common. Regular exercise is now seen as a crucial part of cancer rehabilitation.
According to the findings, both resistance training and HIIT can provide survivors with measurable biological advantages:
- Cancer protection: increased myokine release may enhance immune activity and reduce tumour growth risk.
- Reduced inflammation: exercise helps control chronic inflammation linked to cancer progression.
- Better metabolic health: improved blood sugar and fat metabolism reduces risks of obesity, diabetes, and cardiovascular disease.
- Stronger bones and muscles: lowering the chance of fractures and age-related muscle loss.
- Improved brain health: myokines support memory, cognition, and emotional wellbeing.
The Science Behind Myokines and Cancer Protection
Researchers are increasingly interested in the role of exercise-induced myokines in cancer biology. Laboratory studies suggest that myokines can:
- Slow tumour cell growth by interfering with cancer cell signalling.
- Enhance immune system surveillance, making it easier for the body to destroy abnormal cells.
- Improve the tumour microenvironment, reducing the ability of cancer to spread.
Although more research is needed, the fact that a single 45-minute session produced nearly 50 per cent more myokines is a powerful indicator of how exercise can act as a natural, non-invasive therapy.
Practical Advice for Cancer Survivors
If you are a breast cancer survivor considering resistance training or HIIT, here are some practical tips:
- Consult your GP or oncologist before starting any new exercise program.
- Start gradually – even short sessions of 10–15 minutes can trigger benefits.
- Mix strength and cardio – combine resistance training with HIIT for a balanced routine.
- Listen to your body – fatigue is common post-treatment, so rest when needed.
- Work with a physiotherapist or exercise physiologist if you are new to training.
Wider Implications for Public Health
While the study focused on breast cancer survivors, the benefits of myokine release apply to everyone. Whether you are aiming to prevent disease, improve mental health, or simply stay active, both resistance training and HIIT are scientifically proven to:
- Increase metabolic health
- Provide anti-inflammatory effects
- Support bone formation
- Enhance brain function
- Offer cancer protection
This reinforces the message that exercise is medicine – and one of the most powerful tools we have against chronic illness.
Conclusion
The Australian study provides compelling evidence that resistance training and high-intensity interval training (HIIT) do much more than improve fitness. For breast cancer survivors, they may trigger the release of myokines – powerful molecules that enhance cancer protection, metabolic health, bone strength, brain function, and anti-inflammatory balance.
With just one 45-minute session producing a nearly 47 per cent increase in myokines, the research underscores how vital physical activity can be in long-term recovery and disease prevention.
For millions of cancer survivors worldwide, exercise may not just restore strength – it could also serve as a critical ally in keeping cancer at bay.