A study found exercising as infrequently as once a month was linked to improved cognitive function later in life.

A new study led by UCL researchers has found that exercising at least once a month at any time in adulthood is linked to better cognitive functioning in later life.

The study, published in the Journal of Neurology, Neurosurgery, and Psychiatry, looked at data from 1,417 people who completed surveys about their leisure-time physical activity (sports and exercise) over three decades and took cognitive tests at the age of 69.

The research team found that people who reported being physically active at least one to four times a month in five separate surveys, aged 36, 43, 53, 60-64, and 69, had the most significant cognitive effect.

This effect was more significant than for those who reported frequently exercising (more than five times a month) during at least one survey period but who did not necessarily keep this up across multiple surveys.

“Our study suggests that engaging in any leisure-time physical activity, at any point in adult life, has a positive effect on cognition,” said Sarah-Naomi James, PhD, lead author. “This seems to be the case even at light levels of activity, between once to four times a month. What’s more, people who have never been active before, and then start to be active in their 60s, also appear to have better cognitive function than those who were never active.”

The study participants were from the 1946 British Birth Cohort, the UK’s longest-running population-based cohort who were all born in the same week in 1946 and whose health has been tracked throughout their life.

The researchers aimed to investigate if there was a period of life when physical activity was essential for later-life cognitive function, in the same way that cardiovascular health in middle age appears to be more important for later cognitive health than during other times of life.

But, rather than finding that one period of life was more important than others, they concluded that starting some form of physical activity and maintaining it over a long time may be more important than the timing of this activity.

At age 69, study participants took several cognitive tests, including the Addenbrooke’s Cognitive Examination, which assesses overall cognitive state and is used to screen people for cognitive impairment. They also did a word learning test and a visual processing speed test, where they were asked to cross out all instances of a particular letter in a page of text.

The researchers also looked at other factors that might explain the link between exercise and cognitive functioning.

They found that, while a link remained after accounting for many other factors, including mental health and cardiovascular health, half to two-thirds of the association could be explained by education level, childhood cognition, and socioeconomic background.

People who engaged more in physical activity were also more likely to have taken A-levels and gone to university, had parents from a more privileged background, and done better in tests at the age of eight, and these factors may separately contribute to better cognitive function in later life.

However, a separate link remained between exercise and cognitive function, and the researchers said more work was needed to understand this link better.

The research was supported by Alzheimer’s Research UK (ARUK) and the Medical Research Council and involved researchers from the MRC Unit for Lifelong Health & Ageing at UCL and the UCL Queen Square Institute of Neurology.