(Title image: Photo by Annemiek Smegen on Unsplash)
Following up on my “Exercise and Cancer Cells” post from September 2025, here is another paper by the same authors that was published this month that offers more evidence about the importance of exercise for cancer survivors.
This study by Bettariga et al. (2026, Med Sci Sports Exer) investigated what effect different types of exercise would have on the production of myokines in breast cancer survivors. Why myokines? Because myokines are chemicals released during a muscular contraction. Once in the bloodstream they have various effects on the human body, but the most important for our discussion is that some myokines have been shown to decrease the growth of cancer cells, although the mechanism by which they do that is still unclear.
(Photo by Robert Stump on Unsplash)
This study compared resistance training against high-intensity interval training, or HIIT. For twelve weeks, twenty-eight breast cancer survivors engaged in either resistance training or HIIT, three days per week. Exercise was performed at moderate-to-high levels of intensity, which means that the participants were challenged by the activities.
At the end of the twelve weeks, regardless of which exercise group the subjects were in, the cancer-busting myokines circulating in their bloodstreams had increased by as much as 15%; both resistance training and HIIT were equally effective. Furthermore, when serum taken from the study participants was applied to metastatic (in this case, triple-negative) cancer cells in the lab, there was a 22-25% reduction in the growth of the cells.
These are excellent results. While the study group (28 participants) was quite small and additional research with a larger set of subjects should be done, the effect of exercise was striking.
As mentioned above, the exercise was medium-to-high intensity. What exactly this means for each individual will vary, as intensity is specific to the exerciser and depends a lot on their current fitness levels. For this study, none of the participants had exercised in the previous three months, so they weren’t gym rats to start out with. Their results were still significant.
(Photo by LOGAN WEAVER | @LGNWVR on Unsplash)
As I’ve said in previous posts, being diagnosed with cancer leaves you feeling out of control and powerless about your own body. It can feel like things are happening to you and there’s little you can do about it. This is one way that you can effect a positive change and improve your chances of recurrence-free survival, and it is something over which you have control.
The take-home message? There is a constantly-expanding body of scientific literature that supports maintaining as high a level of physical activity as you personally can, while still respecting the limitations that your body may have. Start slowly, increase intensity gradually, keep going…and don’t ever stop.
REFERENCES
Reader-Friendly Article:
Bettariga F (January 6, 2026) “How Exercise May Suppress Cancer Growth.” Active Voice|ACSM. https://acsm.org/active-voice-how-exercise-may-suppress-cancer-growth/
Research Study:
Full publication (Abstract available without journal access)
Bettariga F, Taaffe DR, Crespo-Garcia C, Clay TD, De Santi M, Baldelli G, Adhikari S, Gray ES, Galvão DA, Newton RU (2026) Effects of Resistance versus High-Intensity Interval Training on Myokines and Cancer Cell Suppression in Breast Cancer Survivors: A Randomized Trial. Med Sci Sports Exer, 58, 1-9.
https://journals.lww.com/acsm-msse/abstract/2026/01000/effects_of_resistance_versus_high_intensity.1.aspx
PubMed Listing
https://pubmed.ncbi.nlm.nih.gov/40903011/
Frantic Shanti 