Slow walkers have slower brains, age faster
WASHINGTON, Oct 12: Ambling along at a leisurely pace might seem like an ideal anti-stress strategy, but if slow-and-steady is your usual speed, it could be an indication that you're aging more quickly than someone with a faster gait. Walking slowly could be a sign you're more likely to get sick in later life, according to new research.
Of all human activities, few are so readily credited with enhancing the power of the mind as going for a good walk. However, those who assume that strolling along at a gentle pace is the hallmark of superior intellect should think again, scientists have said.
The team at Duke University in North Carolina said genetic factors may explain the link between walking speed, brain capacity and physiological health, or that better brain health might promote physical activity, leading to better walking speed.
The 904 New Zealand men and women who were tested at 45 were tracked from the age of three, each undergoing multiple tests over the years.
The long-term data collection enabled researchers to establish that toddlers with lower IQ scores, linguistic ability, capacity to tolerate frustration, motor skills and emotional control tended to have slower gait-speeds by middle age.
MRI exams during their final assessment at 45 showed the slower walkers tended to have lower total brain volume, lower mean cortical thickness, less brain surface area and higher incidence of white matter "hyperintensities," small lesions associated with small vessel disease of the brain.
Doctors have long used walking speed to gain a quick and reliable insight into older people's cognitive capability, as it is increasingly recognized that gait is associated with not only musculoskeletal mechanisms but also the central nervous system.
Researchers found 45-year-olds who naturally walked slowly had brains and bodies that showed signs of "accelerated ageing" on a 19-measure scale. Their lungs, teeth and immune system were all in worse shape than people of the same age who walked faster.
They also had lower total brain volume, less brain surface area and more small lesions in the brain, which is normally indicative of someone older.
Slower walkers also looked older in the eyes of a panel of eight people who assessed each participant's "facial age" from a photograph.
Scientists could work out how fast someone would walk in middle-age by looking at their brains when they were just three years old. Scores on their IQs, their ability to understand language, motor skills and emotional control could predict their walking speed at 45, according to the paper published in Jama Network Open journal.
There was a difference of 12 IQ points on average between children who grew up to be slowest (with a mean gait speed of 1.21 metres per second) and fastest (with a mean gait speed of 1.75 metres per second).
Scientists believe this is because the ability to walk depends on the interplay of many organ systems. They also believe cognitive functions like memory and walking speed could be associated.
"A person's walking speed depends on the function of all these systems working smoothly together, and reduced walking speed can be a sign of advanced ageing and deteriorating function of these organ systems," said senior author Terrie E Moffitt from Duke University and King's College London. "This inexpensive and quick test tells us a lot about their inner health, and how fast their organ systems and brains are ageing towards later diseases."
Dr Moffitt added: "Doctors know that slow walkers in their seventies and eighties tend to die sooner than fast walkers their same age. But this study covered the period from the preschool years to midlife, and found that a slow walk is a problem sign decades before old age." -INDEPENDENT