Physical fitness is associated with cortical grey matter and total grey-matter volumes in elderly men at increased risk for Alzheimer’s disease. However, there’s no such association for women fitting the same profile.
That’s according to a Scandinavian study published online Jan. 6 in Age and Ageing, the journal of the British Geriatrics Society.
In introducing their findings, researchers from the University of Eastern Finland, the Karolinska Institute in Sweden and other institutions in those two countries note that cardiorespiratory fitness (CRF) is known to be associated with larger brain volumes.
What’s been less clear is whether differences exist between the sexes in this regard, particularly in men and women considered to be at increased risk for Alzheimer's disease, the authors point out.
Drawing data from the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), the team looked at a subset of individuals with cognitive performance at the mean level or slightly lower than expected for age according to Finnish population norms.
They looked at the cases of 39 randomly selected men and 29 women aged 61 to 75 years matching these criteria.
The team assessed CRF as peak oxygen consumption (VO2peak) as measured during high-intensity exercise on a cycle ergometer, and they performed brain structural imaging using a 1.5T MRI scanner.
In their journal article, the researchers report that, in men, VO2peak was associated with cortical grey-matter volume (β = 0.56, P = 0.001) and total grey-matter volume (β = 0.54, P = 0.001).
In women, they found no associations between VO2peak and brain volumes.
Additionally, VO2peak accounted for 23 percent and 1 percent of total variance of cortical GM volume as well as 25 percent and 4 percent of total variance of total GM volume in men and women, respectively.
Hence the team’s conclusion: “CRF is associated with cortical grey matter and total grey matter volumes in elderly men at increased risk for Alzheimer’s disease, but not in women.”