Take a hike: It could lead to a healthier brain, a new study says

Could the key to a healthier brain and body be a brisk walk?

Researchers from the University of Münster, Germany have found that faster walkers have better-performing, healthier brains. Analyzing the brain scans of 1,200 volunteers, the team of psychiatrists and statisticians found that walking speed is associated with enhanced brain health and cognitive function.

For the study, the researchers used open data from the Human Connectome Project, a centralized database of volunteers’ brain scans, based at the University of Washington in St. Louis, Mo. Ethically reviewed by the university, the data bank allows scientists from around the world to conduct their own research on its findings.

The Münster team studied volunteers who had their brains scanned using magnetic resonance imaging (MRI). Among other tasks, the volunteers, at the time of the scans, had been asked to walk as quickly as they could, for two minutes. How far they walked was recorded, and the volunteers also took a number of tests — for memory, sharpness, judgment and reasoning — to measure mental performance.

Using rigorous statistical analysis, the team at Münster screened out other variables, such as obesity and age, and determined that physical fitness was associated with better performance on the cognitive tests. What’s more, volunteers who walked farther in two minutes had greater “microstructural integrity” of white matter in their brains. In other words: better walking performance was associated with a healthier brain.

“White matter” acts as an insulator for nerve fibres in the brain, ensuring nerve signals pass quickly and smoothly from one part of the brain to the other. White matter is mostly made up of lipids (fat cells), giving it its whitish colour. It acts “like electrical wiring insulation,” explained Dr. Jonathan Repple, co-ordinator of the research team at the University of Münster. By looking at the volunteers’ brain MRIS, he told the National Post, the team was able to measure the health of white matter.

Once the team had collected data on walking speed, brain function and cognition performance, they moved on to the next challenge: statistical analysis. The team included an economist and statistician, Stella Martin, who helped run complex statistical procedures called linear regressions, to see how the data was related. She repeated analyses to see if other variables besides physical fitness, such as body mass index, affected the results.

What they found astounded them: volunteers who walked farther in the two- minute test had greater concentrations of white matter and had higher test scores on the cognitive tests. What’s more, white matter was correlated with better cognitive performance. Fitter people had better insulation on their brain wiring, reported Dr. Repple.

“It seems like the wire is better insulated in people who are physically active and fit,” he said. “These seem to be better-working people who are actively fit.”

Why would this be?

“Fit people have better blood circulation and a better regulated immune system, leading to less inflammation in the brain. The nerve fibres aren’t being attacked,” he said.

“It sounds stupid,” Martin said, but the two-minute walking test is “highly externally validated and highly correlated” with other measures of physical fitness. “It’s a great measure … of people’s fitness level."

While previous studies have shown connections between exercise and brain health, they have relied on small samples, making the results less generalizable. This study, which used some 1,200 volunteers, allowed the research team to control for interfering variables.

Physical fitness could potentially help with mental decline in old age. “A basic level of fitness seems to be a preventable risk factor for brain health,” Repple says.

The University of Münster’s study confirms other reports connecting the benefits of walking. According to Harvard Health, walking can reduce the risk of cardiovascular problems by 31 per cent and cut the risk of dying by 32 per cent: “Walking and other moderate exercise programs also help protect against dementia, peripheral artery disease, obesity, diabetes, depression, colon cancer and even erectile dysfunction.”

In fact, walking is so important that the U. S. Surgeon General has called on people to take it up. Walking is a “powerful public health strategy,” the Surgeon General’s office noted. It can reduce illness from chronic diseases and premature death, and lower levels of anxiety and depression among students.

So, what about the researcher themselves? Do they walk the walk?

“Our team didn’t go for walks,” Martin said with a laugh. “The Town of Münster is known for cycling. When we go to work we go there by bike.”