One in three breast cancer survivors will experience cognitive problems, which can include difficulties with attention, memory, processing speed and other aspects of thinking. A September 30, 2026 study published in the Journal of the National Cancer Institute reveals that a 12-month remote exercise intervention was associated with improvements in attention among breast cancer survivors, and a companion study suggests exercise may also slow epigenetic aging.
In Plain English: The Clinical Takeaway
- Targeted Cognitive Gains: A modest, remote exercise routine focusing on moderate-to-vigorous physical activity yields measurable improvements in attention span among breast cancer survivors.
- Molecular Impact: Biological aging markers, measured via epigenetic clocks, changed much more slowly in the exercising cohort over a 12-month period compared to a wellness control group.
- Accessible Interventions: Utilizing fitness trackers and individualized coaching to work toward 150 minutes of weekly activity provides a viable pathway to support post-treatment recovery.
Randomized Trial Design and Cognitive Outcomes
The research, originating from the University of California San Diego including members of the Moores Cancer Center, evaluated 253 breast cancer survivors. Every participant had completed active treatment while reporting baseline cognitive difficulties and low levels of physical activity. Researchers randomized subjects into two cohorts: a remotely delivered exercise group utilizing fitness trackers, and a health and wellness group receiving regular contact with a health coach devoid of exercise coaching.
The intervention targeted 150 minutes of moderate-to-vigorous physical activity per week. While both study arms showed meaningful improvements on all cognitive measures, the exercise cohort achieved superior improvements in attention at six and 12 months. Memory scores showed greater improvement at six months, though that benefit was not maintained at 12 months. Executive function and processing speed revealed no significant differences between the two groups.
The real-world significance of these discoveries was underscored by Sheri Hartman, PhD, a professor at the UC San Diego Herbert Wertheim School of Public Health and Human Longevity Science, member of Moores Cancer Center, and lead author of the study. “Attention is central to our everyday activities. It helps us follow conversations, absorb information and complete tasks without making errors, so the sustained improvements we saw in this trial is particularly encouraging,” Hartman noted, adding that participants achieved this benefit with a modest, attainable increase in physical activity.
| Metric / Parameter | Exercise Group (Remote Tracking & Coaching) | Health and Wellness Control Group |
|---|---|---|
| Participant Sample Size | Subset of 253 total survivors | Subset of 253 total survivors |
| Target Physical Activity | 150 minutes/week of moderate-to-vigorous activity | Wellness coaching without exercise coaching |
| Attention Outcomes | Greater improvement at 6 and 12 months | Meaningful improvement |
| Epigenetic Aging Markers | Changed by about 1 month over the 12-month study | Changed by nearly 10 months over the 12-month study |
Cellular Level Changes and Epigenetic Clock Analysis
A companion study nested within the primary trial examined blood samples from 124 participants at baseline, six months, and 12 months. Investigators deployed epigenetic clocks to evaluate biological age based on DNA methylation patterns, distinguishing chronological years lived from biological markers of aging. At enrollment, participants across both arms possessed epigenetic ages averaging about 8.7 years older than their chronological age.
Over the 12-month observation window, biological aging markers diverged. The health and wellness control cohort showed nearly 10 months of epigenetic aging markers, whereas the exercise group showed about one month. Furthermore, faster epigenetic aging was associated with less improvement in attention and worse self-reported cognition across both groups.
The two-tiered impact of the research was pointed out by Paula Desplats, co-senior author of the companion study, adjunct professor of neuroscience at UC San Diego School of Medicine, and professor of neurology at The Ohio State University. “What is particularly striking about these findings is that the effects of exercise were measurable both at the molecular level and in cognitive performance,” Desplats stated, pointing out that modest physical activity may influence biological processes that help keep the brain healthy.
References
- Hartman, S., et al. (2026). Randomized clinical trial of a 12-month exercise intervention on cognitive health in breast cancer survivors. Journal of the National Cancer Institute.
- Desplats, P., et al. (2026). Epigenetic aging markers and the impact of physical activity in breast cancer survivorship. Journal of the National Cancer Institute.
Disclaimer: This article is for informational purposes only and does not substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified physician with any questions regarding a medical condition.
