Midlife workouts could push brain aging in a younger direction

A year can feel like a long time when you worry about your future memory. It can also pass in a blur of work, family, and stress. New research suggests that what you do with that year may leave a mark on your brain.

Scientists at the AdventHealth Research Institute report that a steady aerobic exercise routine helped healthy adults end the year with brains that looked biologically younger on MRI scans. The work adds fresh evidence that midlife habits may shape how your brain ages.

The study focused on “brain age,” an MRI-based biomarker that estimates how old your brain appears compared with your actual age. The researchers tracked “brain-predicted age difference,” also called brain-PAD. A higher brain-PAD means an older-appearing brain, and prior research has linked higher brain-PAD with poorer physical and cognitive function and a higher risk of death.

The clinical trial enrolled 130 healthy adults ages 26 to 58. Researchers randomly assigned them to one of two groups. One group followed a moderate-to-vigorous aerobic exercise program. The other group kept their usual routines, serving as the control.

The exercise plan stayed close to familiar health guidance. Participants completed two supervised 60-minute sessions each week in a laboratory. They also did home-based workouts to reach about 150 minutes of aerobic activity per week. The program aligned with the American College of Sports Medicine’s physical activity guidelines.

The team measured two main outcomes at the start and at the end of the 12 months. They scanned participants’ brains using MRI. They also measured cardiorespiratory fitness using peak oxygen uptake, known as VO2peak.

“We found that a simple, guideline-based exercise program can make the brain look measurably younger over just 12 months,” said Dr. Lu Wan, lead author and data scientist at the AdventHealth Research Institute. “Many people worry about how to protect their brain health as they age. Studies like this offer hopeful guidance grounded in everyday habits. These absolute changes were modest, but even a one-year shift in brain age could matter over the course of decades.”

After 12 months, the exercise group showed a measurable reduction in brain-PAD. On average, brain-PAD dropped by about 0.6 years. That suggests a younger-appearing brain at follow-up.

The control group moved in the opposite direction. Their brains appeared about 0.35 years older on average. That increase did not reach statistical significance, according to the summary. Still, when researchers compared the groups, the difference in brain age came out to nearly one year in favor of the exercise group.

“Even though the difference is less than a year, prior studies suggest that each additional ‘year’ of brain age is associated with meaningful differences in later-life health,” said Dr. Kirk I. Erickson, senior author of the study and a neuroscientist and director at AdventHealth Research Institute and the University of Pittsburgh. “From a lifespan perspective, nudging the brain in a younger direction in midlife could be very important.”

The team also explored why exercise might shift brain-PAD. They looked at several possible pathways: changes in fitness, body composition, blood pressure, and levels of brain-derived neurotrophic factor, or BDNF, a protein involved in brain plasticity.

Exercise improved fitness in a clear way, based on VO2peak. Yet none of the measured pathways statistically explained the change in brain-PAD inside this trial. In other words, the researchers saw the brain-age shift, but their tested variables did not account for it.

“That was a surprise,” Wan told The Brighter Side of News. “We expected improvements in fitness or blood pressure to account for the effect, but they didn’t. 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.”

Many studies on exercise and brain health focus on older adults. Those studies often start after age-related brain changes have already stacked up. This trial aimed earlier, in early to mid-adulthood, when changes may be quieter but still meaningful.

That timing matters because prevention often works best before problems appear. A small shift today might feel modest. Across decades, it could become a bigger story.

“Intervening in the 30s, 40s and 50s gives us a head start,” Erickson 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.”

The researchers also urged caution about what the findings can and cannot promise. The volunteers were healthy and relatively well educated. The observed changes in brain age were modest. The authors also said larger trials and longer follow-ups will need to test whether exercise-linked reductions in brain-PAD translate into lower risk of stroke, dementia, or other brain diseases tied to aging.

Still, the study speaks to a question people ask in quiet moments, often before a birthday or after a family member struggles: What can you do now to protect your brain later?

“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; 150 minutes per week of moderate-to-vigorous aerobic activity; may help keep the brain biologically younger, even in midlife.”

For everyday life, the message stays simple and realistic. The program did not demand extreme training. It used a guideline-based target of about 150 minutes of aerobic exercise per week, plus two supervised sessions. That structure may help people who struggle with consistency, since it mixes accountability with flexible home workouts.

For research, the study raises a productive mystery. Exercise improved fitness, but the tested pathways did not explain the brain-age change. That pushes scientists to look deeper at other mechanisms, including subtle shifts in brain structure, inflammation, vascular health, or other molecular factors mentioned by the authors. Future trials can also test whether changes in brain-PAD predict later outcomes, including cognitive decline and dementia risk.

For public health, the work supports earlier action. Many people wait until older age to focus on brain health. This trial suggests midlife may offer a chance to build resilience sooner, when prevention could yield larger lifelong benefits. Even modest changes, repeated over years, may accumulate into meaningful protection.

Research findings are available online in the Journal of Sport and Health Science.

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