A larger brain usually means a healthier brain.
The differences were most pronounced in parts of the brain involved in thinking and memory. These areas often shrink with age, contributing to cognitive decline and the risk of dementia.
“This is an interesting finding and adds further fuel to the idea that being physically active helps maintain brain volume throughout the lifespan,” said David Reichlen, professor of biological sciences and anthropology at the University of Southern California. It will give you,” he said. He studies brain health but was not involved in this new study.
The results also have practical implications for which types of exercise are best for brain health and how much exercise you actually need.
A little exercise, a big brain
“We wondered, what would we see if we chose very low threshold motion?” Cyrus, an associate professor of radiology and neurology at Washington University in St. Louis, who led this new study. A. Raji said.
He and his colleagues were well aware that exercise is good for the brain, especially as we get older.physically active elderly much less likely Being sedentary is more likely to cause Alzheimer's disease and other types of memory loss and cognitive decline.
But he also knew that in the real world, not many people exercise. He says, “I hear that you need 10,000 steps a day, or 150 minutes a week. But these goals are very difficult to achieve.
He and his colleagues wondered whether exercising less, or even much less, could help build a healthier brain.
For example, how about 25 minutes of exercise per week, one-sixth of the 150 minutes recommended by most companies? official exercise guidelines?
“For most people, that seemed like an achievable amount,” Raji said. But does it affect the brain?
He and his colleagues looked at existing brain scans of 10,125 mostly healthy adults of all ages who visited academic medical centers for diagnostic tests. These patients previously provided information about their medical history and how often they had engaged in strenuous exercise in the past 2 weeks.
The researchers divided them into those who exercised at least 25 minutes a week and those who did not.
Then, with the help of artificial intelligence, they began comparing scans and exercise habits to look for differences in brain volume, or the amount of space taken up by the brain and its components. Generally, larger volumes are desirable.
A clear pattern quickly emerged. Men and women of all ages who exercised at least 25 minutes a week were shown to have larger brain volumes than those who did not. The difference wasn't that big, but it was especially noticeable when researchers looked deeper inside the organ, Raji said.
They found that people who exercised had more volume in all types of brain tissue, including gray matter, which is made up of neurons, and white matter, the brain's wiring infrastructure that supports and connects thinking cells. did.
Looking more closely, people who exercised tended to have larger hippocampi, a part of the brain essential for memory and thinking. It typically shrinks and deflates with age, affecting reasoning and memory abilities.
They also exhibit larger frontal, parietal, and occipital lobes, both of which indicate a healthy, robust brain.
Moderate exercise is best for the brain
Raji said it was “surprising and encouraging” to see such widespread effects on the brains of people who exercise less.
Of course, this study is relevant, meaning it shows a link between exercise and brain health, but it doesn't necessarily mean exercise causes improvements. So it's possible that other lifestyle factors or genetics are at play, or that people with bigger brains just happen to prefer exercise.
But given the number of scans and the wide age range, Raji said the effects of exercise on people's brains are real and direct, and could help them maintain proper thinking skills as they age. thinking.
It is impossible to say from this study exactly what changes exercise brings about in the brain. But Raji and his colleagues believe that exercise also promotes the release of various neurochemicals that reduce inflammation in the brain and promote the production of new brain cells and blood vessels.
In fact, exercise appears to help build and store the brain's “structural reserve.” This is a buffer of extra cells and materials that may provide some protection against the otherwise inevitable decline in brain size and function that accompanies aging. Our brains can still shrink and become confused over the years. But when you exercise, this slow fall starts from a higher baseline.
Perhaps best of all, the most effective exercise in this study was relatively gentle. People who exercised moderately, meaning they were able to talk while exercising, had slightly larger brain volumes than those who exercised more vigorously, such as by running briskly.
However, the number of people who exercised vigorously was so small that the comparison was questionable, Raji said, and their brain volumes were still larger than those who did little or no exercise.
Overall, he said, any type of exercise, even in small amounts, is likely to be a “very good idea” for brain health.
Raichlen agrees. “Studies like this continue to provide strong evidence that even small amounts of physical activity can impact brain health, and it's never too early or too late to start.” I am.”
Have fitness questions? Email [email protected] I may answer your question in a future column.
