Middle aged people who walk slowly may have “older brains”, research suggests.
Nearly 1,000 45-year-olds underwent gait assessments and MRI scans by scientists at Duke University, in the US.
The slower walkers had brains that appeared five years ‘older’ than their speedier counterparts, with a reduced volume, thickness and surface area.
The amblers also scored worse on 19 health assessments, which looked at everything from blood pressure and BMI to inflammation and gum health, the results show.
Although unclear exactly why this occurs, the scientists believe brain function and walking speed may be controlled by the same set of substances.
People with healthier brains may also be more likely to live well by not smoking and exercising regularly, they added.
“The thing that's really striking is this is in 45-year-old people, not the geriatric patients who are usually assessed with such measures,’ lead author Dr Line Rasmussen said.
“Doctors know slow walkers in their seventies and eighties tend to die sooner than fast walkers their same age.
“But this study found a slow walk is a problem sign decades before old age.”
While walking may seem simple, it actually involves a complex interplay between a person’s bones, muscles, sight and central nervous system, the scientists wrote in the journal JAMA Network.
Our pace naturally declines in old age, but slowing down has also been linked to everything from heart disease and dementia to an early death.
Less was known about the link between walking speed and health in mid-life. To learn more, the scientists started looking at 904 people when they were just three years old, with them then being followed up to middle age.
Results show the children with a low IQ, poor communications skills and even weak ‘emotional control’ were more likely to be slow walkers decades later.
When the participants reached 45, MRI scans showed the slow walkers had a lower brain volume.
Reduced volume to the parts of the brain that control memory, the hippocampus, and emotion, the amygdala, has previously been linked to dementia.
The slow walkers also had thinner cortices, which regulate everything from intelligence and personality to processing the five senses.
A leisurely pace was also linked to reduced brain surface area, which suggests shrinkage, as well as a greater number of ‘hyperintensities’.
Hyperintensities are small lesions that can be a sign of nerve cell loss, as well as tissue damage triggered by poor blood and oxygen supply.
On top of the brain scans, the participants also had 19 health assessments. The results again showed the slower walkers came out worse.
In the final part of the experiment, eight people were asked to estimate the age of the participants from photographs.
Perhaps adding insult to injury, the slower walkers were deemed to be older than they were.
The scientists hope their findings will lead to walking speed one day being used to prevent age-related disease.
With prevention being better than cure, spotting warning signs early may make people more receptive to medical interventions, they wrote.
“We may have a chance here to see who's going to do better health-wise in later life,” Dr Rasmussen said.
MRI scans were not taken at the start of the experiment due to the technology only being invented when the participants were five.
However, walking speed in childhood could indicate a youngster’s health down the line, the scientists said.
“It’s a shame we don’t have gait speed and brain imaging for them as children,” Dr Rasmussen said.
“We may have a chance here to see who’s going to do better health-wise in later life.”