New study shows walking can help fight dementia

Alzheimer’s disease is the most common form of dementia that slowly kills off brain cells. According to a new study, activities like walking may actually protect the brain from shrinking and preserve memory in elderly people.

“Brain size shrinks in late adulthood, which can cause memory problems,” study researcher Kirk I. Erickson, PhD, of the University of Pittsburgh, says in a news release.

Erickson and his team started documenting the physical activity and cognitive (or thinking) patterns of approximately 300 adults in 1989. The team also had access to brain scan results from four years previously which measured the amount of “grey matter” in their brains. At the start, all participants were in good cognitive health, they averaged 78 years old and about two-thirds were women. The researchers charted how many blocks each person walked in a week. Nine years later, the participants were given a MRI scan to measure their brain size.

By the time the mental testing was finished, 116 of the participants – or 40% – had developed some degree of dementia or cognitive impairment. But those who had walked the most were half as likely to be experiencing memory problems. However, walking more than one mile every day did not further improve brain volume.

The research indicates that nine miles a week – or in the urban US terms of the data, 72 Pittsburgh city blocks – is the optimum distance for “neurological exercise”.

The research was released online on 13 October in Neurology, the medical journal of the American Academy of Neurology.