A steady routine of aerobic exercise can make the human brain appear nearly a year younger biologically, according to new research suggesting that physical activity may reverse the clock on cognitive ageing.
The study, published in the Journal of Sport and Health Science, found that adults who committed to a one-year aerobic training program showed a measurable reduction in their “brain age”, a biomarker derived from MRI scans that estimates the brain’s biological health compared to its chronological age.
While previous research has focused on exercise preventing decline in the elderly, this trial targeted healthy adults aged 26 to 58. The findings offer compelling evidence that intervening in midlife could provide a critical “head start” against dementia and cognitive decline.
“We found that a simple, guideline-based exercise program can make the brain look measurably younger over just 12 months,” said Dr. Lu Wan, data scientist at the AdventHealth Research Institute and lead author of the study.
Turning back the clock
The clinical trial involved 130 healthy volunteers who were randomly assigned to either a moderate-to-vigorous aerobic exercise group or a control group that maintained their usual lifestyle. The exercise group performed 150 minutes of activity per week — aligning with standard health guidelines — including two supervised sessions.
After 12 months, the results showed a distinct divergence.
- The exercisers: Their brains appeared roughly 0.6 years younger on average.
- The control group: Their brains appeared about 0.35 years older.
The net difference between the groups was nearly a full year.
“From a lifespan perspective, nudging the brain in a younger direction in midlife could be very important,” said senior author Dr. Kirk I. Erickson. “If we can slow brain ageing before major problems appear, we may be able to delay or reduce the risk of later-life cognitive decline.”
The ‘hidden’ mechanism
Interestingly, the study deepened the mystery of how exercise rejuvenates the brain. While the participants got fitter — improving their peak oxygen uptake (VO2peak) — statistical analysis showed that neither improved fitness, weight loss, nor blood pressure was the direct cause of the “younger” brain appearance.
“That was a surprise,” Wan admitted. “Exercise may be acting through additional mechanisms we haven’t captured yet, such as subtle changes in brain structure, inflammation, or vascular health.”
Regardless of the mechanism, the prescription remains accessible to almost everyone. “People often ask, ‘Is there anything I can do now to protect my brain later?’” Erickson said. “Our findings support the idea that following current exercise guidelines… may help keep the brain biologically younger.”
