Scientists have now found gait speed can be used to measure how quickly a person is ageing. Studies show that the number of diagnosed gait disorders vastly increases from 10 % in people aged 60–69 years, to more than 60 % in groups of people aged over 80 years.
Recently studies found that not only did their slower subject walkers look older, but they generally had smaller brains too.
Interestingly, this slow gait speed has now been linked to a higher risk of neurocognitive functional decline, leading to conditions such as dementia.
A recent study in New Zealand followed 1000 people born in the 1970s to the age of 45. The test group had both physical and brain function assessments and scans, as well having cognitive tests throughout their childhood.
This study used the gait speed test not just on elderly people, but also on young mid-life adults.
Terrie E Moffitt of Kings College London, a specialist in developmental psychopathology, ageing, and neuropsychology, stated about these findings that "This study found that a slow walk is a problem sign decades before old age".
The study found there was a large difference in the people’s walking speed, even at the age of 45. Slower walkers had older looking brains, and their teeth, lungs and immune systems were more damaged by age than those with a faster gait speed. Therefore, slower gait was correlated with accelerated ageing.
Amazingly, using data collected for intelligence, motor and language skills from the subjects when they were 3 years old, the scientists found they could predict what the person’s walking speed would be when they were 45.
It was found that faster walkers around the age of 45 had on average 12 IQ points higher in their childhood than the slowest walkers.
Scientists are now investigating interventions and treatments that could slow human ageing. One current example is a low-calorie diet, which has proven that when the body is under slight stress from lack of food, this can lead to a reduction in the ageing process.
Metformin, a drug commonly used to treat type 2 diabetes, has also been shown to slow ageing in model organisms. Fascinatingly, Metformin reduces age-related diseases such as neurodegenerative disease and cancer, and so is a prospective target for anti-ageing investigations.