Exercise is good for you—that’s a no brainer. But scientists are finding increasing evidence it’s crucial for a healthy brain. A new study that measured how physical fitness affects the brain has shown that the lower the activity level, the faster the deterioration of necessary fibers in the brain.
Researchers at UT Southwestern’s O’Donnell Brain Institute focused their study on white matter, the fibrous part of the brain that controls communication between cells.
The findings build on a body of evidence that is all too clear to ignore: Exercise is necessary for brain health. What makes the study stand out is that the researchers did not rely on participants to report their own fitness levels—they measured physical fitness with a test called maximal oxygen uptake, which measures how much oxygen a person can take in during vigorous exercise. They then gave participants tests that measured cognition and memory. What they found was a correlation between brain health, physical fitness and levels of white matter. The lower the physical activity, the weaker the white matter and the worse participants performed on tests.
“This research supports the hypothesis that improving people’s fitness may improve their brain health and slow down the aging process,” said Dr. Kan Ding, a neurologist from the Peter O’Donnell Jr. Brain Institute who authored the study.
In 2013, the same team found that the brain’s messaging system is more efficient in adults that exercise more. These two studies add to a growing body of research that convinced the American Academy of Neurology to recommend exercise as a treatment for mild cognitive impairment over drugs. But while studies on exercise answer some questions about dementia prevention, they also leave plenty unanswered: What type of exercise is necessary to protect the brain? How long? How much? Is exercise protective for people already showing signs of Alzheimer’s?
“Evidence suggests that what is bad for your heart is bad for your brain. We need studies like this to find out how the two are intertwined and hopefully find the right formula to help prevent Alzheimer’s disease,” said Dr. Rong Zhang of University of Texas Southwestern.
The research team hopes to pursue the answers to those questions, especially in light of the fact that almost 100 percent of Alzheimer’s drugs in clinical trials fail.
“A lot of work remains to better understand and treat dementia,” said Ding. “But, eventually, the hope is that our studies will convince people to exercise more.”
This study was published in the Journal of Alzheimer’s Disease.