Resistance Exercise Training Slows Down Brain Aging

Using brain clock models that analyzed MRI images of the brains of elderly people who underwent one year of resistance training, researchers concluded that both heavy and moderate resistance training slow brain aging [1].

The broad benefits

Exercise has been linked to many benefits, such as lowering blood pressure, slowing down cancer progression, preventing fitness decline in old age, and lowering biological age. We have also recently reported an association between exercise variety and a lower risk of mortality.

Exercise has also been linked to better brain health; studies suggest that it can improve cognition in older people, offer a protective effect against Alzheimer’s disease (however, only to a certain point), and, in some cases, help to alleviate age-related cognitive decline. The impact of exercise on brain structures was also investigated. Exercise has been shown to affect brain volume, specifically the hippocampus [2, 3]. However, there is a variability in how individuals respond to exercise [4]. Additionally, those previous studies have notable limitations, such as short-term interventions, and often investigate only a single brain region, which can miss global changes in the brain.

The authors of this study decided to address some of those shortcomings. Their study included 309 adults, between 62 and 70 years old, who were randomized into three groups: heavy resistance training (HRT), moderate-intensity resistance training (MIT), and a non-exercise control group. The exercise groups followed a 1-year program combining resistance and functional training to improve strength, endurance, and balance. Then, the researchers assessed how the training impacted the brain health.

Global changes with local enhancers

Previous studies suggested that specific brain regions are involved in exercise-mediated cognitive improvement [2]; however, they didn’t determine whether only certain regions are affected or whether exercise affects the brain beyond the identified regions.

In this study, brain connectivity analysis indicated that a year of heavy resistance training, but not moderate-intensity resistance training, resulted in significantly greater activity than in the group that didn’t exercise. Significant clusters of activity were especially evident in prefrontal regions, as well as in motor cortex and superior parietal areas of the brain. Those regions are responsible for such functions as attention, executive control, and working memory [5, 6]. The observed strengthening of connections in those specific brain regions might suggest a mechanism that links exercise and cognitive improvements that should be investigated further.

However, while these effects were more prominent in some brain regions, this study suggests that exercise-related changes were present beyond those specific regions, indicating general improvements in brain health. The researchers also suggest that these broad effects are likely due to exercise-induced “systemic molecular and vascular processes”; however, this remains to be experimentally tested.

Exercising your way to slower brain aging

In the next step, the researchers used recently developed brain clocks, a new class of biomarkers of brain health. Those models combine different imaging modalities, in this case functional magnetic resonance imaging (rs-fMRI), to estimate brain age. The difference between the model’s estimated age and the participant’s chronological age reflects the speed of brain aging. The researchers trained brain clock models on an independent dataset of 2,433 participants in a different study and used those models in the 309 participants of this study.

The brain age gap (BAG), which indicates “whether the brain appears older or younger than the chronological age at a given time point,” decreased in the exercise groups following one year of exercise and one year after the exercise regimen stopped. For the heavy resistance training group, the researchers observed a 1.4-year reduction at one year after the exercise regimen began and a 1.84-year reduction one year after the exercise regimen ended. For the moderate-intensity resistance training group, reductions of 1.39 and 2.26 years were observed at those time points, respectively. As expected, the group that didn’t exercise showed no significant changes in BAGs.

Those results suggest the brains of people who exercised were younger than their chronological age and that the beneficial effects of training are lasting, as the positive impact is seen even a year after the training regimen ended.

Those changes are consistent with the effect sizes reported in other studies examining the impact of lifestyle factors, such as physical activity or education, on the aging brain [7, 8]. Even though such changes appear rather modest, their overall effect is meaningful. As the authors explain: “Given that brain aging is a gradual and cumulative process, differences of this magnitude are considered biologically meaningful and have been linked to improved brain integrity and cognitive performance in older adults.”

Changes in BAGs were also correlated with changes in leg strength but were significant only in the moderate exercise group. The authors offer explanations for why only the moderate-intensity resistance training group shows the association. One of them might be the non-linear dose-response relationship, meaning that higher levels of exercise do not necessarily produce greater effects. There may also be varying baseline fitness levels among study participants, varying individual responsiveness to training, or measurement noise.

Good design with limitations

In summary, the obtained results suggest that both heavy and moderate resistance training slow brain aging, indicating that resistance training, among other modifiable lifestyle factors, can improve brain health in the elderly. What’s more, developing these models allows other researchers to use them to test the impact of other interventions on brain health.

This study, while relatively small, uses a randomized, controlled design, making it a stronger methodological approach than previous cross-sectional studies. However, the results may not be broadly generalizable to everyone, as the study sample consisted of high-income Europeans rather than a representative sample of the population.

Literature

[1] Gonzalez-Gomez, R., Demnitz, N., Coronel, C., Gates, A. T., Kjaer, M., Siebner, H. R., Boraxbekk, C. J., & Ibanez, A. M. (2026). Randomized controlled trial of resistance exercise and brain aging clocks. GeroScience, 10.1007/s11357-026-02141-x. Advance online publication.

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[3] Jonasson, L. S., Nyberg, L., Kramer, A. F., Lundquist, A., Riklund, K., & Boraxbekk, C. J. (2017). Aerobic Exercise Intervention, Cognitive Performance, and Brain Structure: Results from the Physical Influences on Brain in Aging (PHIBRA) Study. Frontiers in aging neuroscience, 8, 336.

[4] von Cederwald, B. F., Johansson, J., Riklund, K., Karalija, N., & Boraxbekk, C. J. (2023). White matter lesion load determines exercise-induced dopaminergic plasticity and working memory gains in aging. Translational psychiatry, 13(1), 28.

[5] Friedman, N. P., & Robbins, T. W. (2022). The role of prefrontal cortex in cognitive control and executive function. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 47(1), 72–89.

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[7] Dunås, T., Wåhlin, A., Nyberg, L., & Boraxbekk, C. J. (2021). Multimodal Image Analysis of Apparent Brain Age Identifies Physical Fitness as Predictor of Brain Maintenance. Cerebral cortex (New York, N.Y. : 1991), 31(7), 3393–3407.

[8] Steffener, J., Habeck, C., O’Shea, D., Razlighi, Q., Bherer, L., & Stern, Y. (2016). Differences between chronological and brain age are related to education and self-reported physical activity. Neurobiology of aging, 40, 138–144.