Physically unfit people ‘may have smaller brains in later life’

A lack of physical exercise has been associated with a higher risk of having a smaller brain in later life, according to a new study.

The research from Boston University School of Medicine saw 1,583 people, with an average age of 40 and without dementia or heart disease, take two treadmill tests 20 years apart, along with MRI brain scans.

Reduction in a person's exercise capacity shown by the treadmill test was linked with a decrease in brain volume two decades later. People whose blood pressure and heart rate went up at a higher rate during exercise also were more likely to have smaller brain volumes.

It was noted that the current study is observational, meaning there is no evidence that the link between poor physical fitness and a loss of brain volume is causal. Nevertheless, it shows there is an association between a lack of exercise and accelerated brain ageing.

Study author Dr Nicole Spartano at the Boston University School of Medicine said: "While not yet studied on a large scale, these results suggest that fitness in middle age may be particularly important for the many millions of people around the world who already have evidence of heart disease."