Why do old people walk slowly

Aging research: those who walk slowly get old faster

You usually only notice that walking is a very complex matter when it is no longer possible. A team led by Line Jee Hartmann Rasmussen from Duke University has found that a person's walk reveals a lot about their health - especially about their biological age - even beforehand. People who are particularly slow on the move apparently have up to five years ahead of their age compared to their contemporaries who are in a hurry. The difference was reflected both in physical fitness parameters such as blood pressure and respiratory volume as well as in the brain structures and cognitive abilities of the test subjects, the working group now writes in the journal »JAMA Network Open«.

Other research groups have already discovered a connection between walking speed and the life expectancy of older people. A slow, unsteady walk is also an indication of dementia. Rasmussen's team was not interested in this age group, but in people who are still quite good on their feet. Almost 1,000 people aged 45 and over had the group march on a treadmill. What is special about them: They were all born between April 1972 and March 1973 in Dunedin, New Zealand, and were examined regularly from the age of three - as part of the Dunedin Multidisciplinary Health and Development Study. Speed ​​measurements were not made at a young age, but motor, intelligence and language tests were. When the researchers compared the results from then with the walking speeds of today, they noticed that the test subjects who did the worst at the age of three were now the slowest on foot. So maybe you can already predict in childhood who will one day "walk slowly" - and get old faster. In photos that only showed the face of the 45-year-old test person, outsiders classified slower walkers as older than “fast walkers”.

This article is included in Spectrum - The Week, 42/2019

Using magnetic resonance imaging (MRI), the working group also took a look into the brains of the 45-year-old test subjects and found that, among other things, the brain of slow walkers had a smaller volume, a thinner cortex and more damage to the so-called white matter (substantia alba) that go along with aging. It would be exciting to know how the subjects' brains changed over time and when this affected their walking speed. Unfortunately, there are no previous walking or MRI images of the subjects. Magnetic resonance tomography was first used on humans in 1977 and was by no means part of the examination standard - especially not in children. The comparison between a child's and an adult's brain would be difficult anyway.

In further tests, Rasmussen's research team noticed that the cognitive abilities of the slowest people had also decreased the most over time. They also had "older" blood and respiratory parameters and performed worse on various movement and coordination tests. Using the many results, the researchers calculated that the slowest test subjects had aged up to five years faster than the fastest. The measurement of the walking speed of middle-aged people could be used for the early detection of various diseases, says Rasmussen's team. Noticing any damage in good time - and ideally repairing it - could help prevent diseases such as Alzheimer's. The investigation would always be simple, cheap and safe.