Exercise benefits both the heart and metabolic health, however, its influence on the brain has been harder to define. Brain aging unfolds quietly, shaped by gradual structural changes that have long been difficult to observe in real time.
A recent clinical trial using brain imaging suggests that regular physical activity may be linked to measurable differences in brain health over time.
The findings come from a randomized clinical trial conducted by researchers at the AdventHealth Research Institute and the University of Pittsburgh.
The trial followed 130 adults ages 26 to 58, who were divided into two groups: one that engaged in a structured aerobic exercise program and another that continued with their usual routines.
Throughout the study, researchers used magnetic resonance imaging to examine changes in brain structure associated with physical activity. Over 12 months, researchers observed clear differences between the two groups.
“We found that a simple, guideline-based exercise program can make the brain look measurably younger over just 12 months,” Dr. Lu Wan, lead author of the study and a data scientist at the AdventHealth Research Institute, said.
According to brain imaging analyses, the exercise group demonstrated a modest reduction in estimated brain age, while the control group showed little to no improvement. When compared directly, the gap between the two groups amounted to nearly a full year in relative brain aging. “These absolute changes were modest,” Wan added, “but even a one-year shift in brain age could matter over the course of decades.”
To better understand why exercise appeared to influence brain age, the researchers examined several potential contributing factors, including changes in physical fitness, body composition, blood pressure and levels of brain-derived neurotrophic factor, which is a protein involved in brain plasticity.
While participants in the exercise group showed clear improvements in fitness, none of these measures statistically accounted for the reduction in brain-predicted age difference, observed during the trial.
“We expected improvements in fitness or blood pressure to account for the effect, but they didn’t,” Wan said. “Exercise may be acting through additional mechanisms we haven’t captured yet, such as subtle changes in brain structure, inflammation, vascular health or other molecular factors.” The findings suggest that the relationship between exercise and brain aging may be more complex than previously understood.
Building on these results, the researchers point to mid-adulthood as a potentially important period for intervention. Brain aging begins long before cognitive symptoms appear, making earlier lifestyle changes more likely to influence long-term outcomes.
“Intervening in the 30s, 40s and 50s gives us a head start,” Kirk Erickson, neuroscientist and senior author of the study, said. “If we can slow brain aging before major problems appear, we may be able to delay or reduce the risk of later-life cognitive decline and dementia.”
Because the study examined healthy adults, researchers stressed that its findings should be interpreted with caution. Longer and larger trials would be necessary to establish whether differences in brain age translate into meaningful protection against neurological disease later in life.
The work contributes to a broader understanding of how behavior plays a role in the brain’s aging across adulthood.
