IF THERE was ever a reason to get off the couch and get moving, here's a doozy ..... couch potatoes could have smaller brains later in life.
A study has shown that poor physical fitness in middle age may be linked to reduced brain volume indicating accelerated brain ageing 20 years later.
For the study, 1,583 people enrolled in the Framingham Heart Study, with an average age of 40 and without dementia or heart disease, took a treadmill test.
They took another one two decades later, along with MRI brain scans. The researchers also analyzed the results when they excluded participants who developed heart disease or started taking beta blockers to control blood pressure or heart problems; this group had 1,094 people.
Exercise capacity was estimated using the length of time participants were able to exercise on the treadmill before their heart rate reached a certain level. For every eight units lower a person performed on the treadmill test, their brain volume two decades later was smaller, equivalent to two years of accelerated brain aging.
When the people with heart disease or those taking beta blockers were excluded, every eight units of lower physical performance was associated with reductions of brain volume equal to one year of accelerated brain aging.
The study also showed that people whose blood pressure and heart rate went up at a higher rate during exercise also were more likely to have smaller brain volumes two decades later.
Lead author Britt M. Burton-Freeman from Illinois Institute of Technology said the study was observational. It does not prove that poor physical fitness causes a loss of brain volume; it shows the association.
The study was supported by the National Heart, Lung and Blood Institute, the National Institutes of Health and the American Heart Association and was published in the Feb. 10 online issue of Neurology, the medical journal of the American Academy of Neurology.