Lifelong Exercise May Protect the Brain from Age-Related Decline
A new study from the U.S. National Institute on Aging (NIA) suggests that maintaining regular physical activity throughout life may help prevent brain function decline in middle and older age.
Researchers measured cardiovascular fitness in 125 cognitively healthy adults aged 22 to 94 and examined their brain structure. They focused on white matter, which is made up of myelin—a fatty insulating layer around neurons. Myelin protects nerve cells from damage and speeds up communication between different parts of the brain. The findings, published in Proceedings of the National Academy of Sciences (PNAS), indicate that lifelong exercise could be a promising strategy to promote brain health and reduce the risk of neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
Why Myelin Matters
As people age, myelin naturally declines. This loss can reduce the brain’s ability to process information efficiently and may make nerve cells more vulnerable to damage.
Previous studies have shown that aerobic exercise might help maintain or even increase myelin in adulthood, though the exact biological mechanisms remain unclear.
How the Study Was Conducted
Cardiovascular fitness measurement: Participants’ VO₂max (maximum oxygen consumption) was recorded during treadmill exercise, using a mask connected to equipment that measured oxygen and carbon dioxide levels every 30 seconds.
Brain imaging: MRI scans were used to assess myelin content in various brain regions through advanced mathematical and physical modeling.
Age groups: Participants were divided into four categories—22–39, 40–59, 60–79, and 80–94 years old.
Key Findings
Even small increases in VO₂max were strongly associated with significant increases in myelin content.
The most notable improvements were seen in participants aged 40 and older, suggesting that a lifetime of cardiovascular fitness may pay off in midlife and beyond by protecting brain myelin.
Importantly, participants were not professional athletes, but ordinary people who exercised regularly at varying levels of intensity.
Why It Matters
The study highlights the potential of cardiovascular fitness to support myelin production and maintenance, which could help preserve cognitive function as we age.
According to the authors, promoting regular exercise could become part of a non-drug prevention strategy for age-related brain decline.