Research Summary

Can a Single Exercise Session Trigger Anti-Cancer Effects in Breast Cancer Survivors?

Anthony Calabro, MA

Key Highlights

  • Both resistance training and high-intensity interval training (HIIT) increased serum levels of key anti-cancer myokines.
  • HIIT led to a significantly greater rise in interleukin 6 (IL-6) immediately post-exercise.
  • Serum collected after exercise inhibited growth of breast cancer cells by 19% to 29%.
  • A single bout of exercise may confer immediate anti-tumor effects in breast cancer survivors.

A single bout of either resistance training or high-intensity interval training (HIIT) elicited acute anti-cancer effects in survivors of breast cancer. The study found that both exercise modalities significantly increased serum levels of decorin, interleukin 6 (IL-6), and secreted protein acidic and cysteine rich (SPARC), and that post-exercise serum markedly suppressed the growth of MDA-MB-231 triple-negative breast cancer cells in vitro.

IL-6 levels were significantly higher in the HIIT group immediately after exercise, and cell growth inhibition was greater for HIIT compared with resistance training at this same time point. These findings suggest that both exercise modes may acutely trigger biochemical pathways associated with tumor suppression.

Breast cancer remains the leading cause of cancer-related death among women worldwide. Despite advances in treatment, recurrence continues to affect up to one-third of survivors, emphasizing the need for additional non-pharmacologic strategies to reduce recurrence and mortality. Exercise is widely endorsed as an adjunct therapy for breast cancer management due to its established benefits on fitness, body composition, and quality of life. However, the biological mechanisms linking exercise to improved survival remain incompletely understood.

In this randomized study of 32 patients who survived breast cancer, participants were assigned to perform a single bout of either resistance training or HIIT. Blood samples were obtained before exercise, immediately after (0P), and 30 minutes post-exercise (30P). Serum concentrations of decorin, IL-6, SPARC, and oncostatin M (OSM) were measured, and their effects on MDA-MB-231 cell growth were tested using real-time cellular analysis.

Both interventions were matched for duration (≈ 45 minutes) and intensity (rating of perceived exertion 7–9, corresponding to > 80% one repetition maximum for RT and 70–90% maximum heart rate for HIIT).

Results showed significant within-group increases in decorin, IL-6, and SPARC (ranging from 9% to 47%) immediately post-exercise in both groups. IL-6 and OSM remained elevated 30 minutes after exercise, particularly in the resistance training group for OSM. Between-group analysis revealed that IL-6 levels were significantly higher in HIIT immediately post-exercise (P = .001). Cancer cell growth was significantly reduced in both groups at 0P and 30P, with reductions of 19% to 29% from baseline, and a greater inhibitory effect observed for HIIT at 0P (P = .001). No adverse events were reported, and participants in both groups tolerated the interventions well.

Limitations included the use of only one breast cancer cell line (MDA-MB-231), short-term measurement of biochemical changes, and the inability of in vitro assays to replicate the complexity of in vivo tumor environments. Medication use that could influence immune or myokine responses was also not assessed.

“A single bout of resistance or high-intensity interval training can increase levels of anti-cancer myokines and reduce the growth of MDA-MB-231 cells in vitro in survivors of breast cancer, potentially contributing to a lower risk of recurrence,” the authors concluded. “This highlights the importance of exercise as a treatment with promising anti-cancer effects.”

Reference
Bettariga F, Taaffe DR, Crespo-Garcia C, et al. A single bout of resistance or high-intensity interval training increases anti-cancer myokines and suppresses cancer cell growth in vitro in survivors of breast cancer. Breast Cancer Res Treat. 2025;213(1):171–180. doi:10.1007/s10549-025-07772-w