Research suggests mental and physical activity could preserve thinking ability in different ways depending on whether someone is a man or woman, and there may be a further genetic element to this.
The findings indicate older women might particularly benefit from the way these lifestyle choices affect cognitive reserve, a reservoir of thinking skills and abilities that can protect brain function despite aging and disease.
Women in the study were also disproportionally affected from carrying the APOE4 gene, which is the major genetic risk for late-onset Alzheimer’s disease.
Yet the study, published in the journal Neurology, also suggested mental activities such as reading, or card games might protect thinking speed in both men and women.
“As we have arguably few-to-no effective treatments for Alzheimer’s disease, prevention is crucial,” said researcher Judy Pa, PhD, of the University of California at San Diego, USA.
She added: “To know that people could potentially improve their cognitive reserve by taking simple steps such as going to classes at the community center, playing bingo with their friends or spending more time walking or gardening is very exciting.”
The findings come from 758 Americans, with a mean age of 76.1 years, who were regularly followed up as part in a community-based study and had unimpaired cognition, mild cognitive impairment, or dementia.
Participants were recruited in three waves, in 1992, 1999 and 2009, filled in lifestyle questionnaires and underwent a battery of neuropsychological tests. A subset also receiving magnetic resonance imaging (MRI) brain scans.
The researchers found that physical activity, converted into metabolic equivalents, was linked with greater thinking speed reserve only in women.
Cognitive activities such as reading magazines, newspapers and books, going to classes or playing cards, games or bingo were associated with greater speed reserve in the group as a whole.
These mental activities also showed a trend towards being linked with greater memory reserve but only in women. Physical activity did not affect this measure in either sex.
Only in women did being an APOE4 carrier impact on the relationship between physical activity and speed reserve, and between mental activity and both speed and memory reserves.
The researchers note that, there were no differences between men and women in levels of reading or card playing, women did take part in more group-based classes.
These incorporate a social component and that may engage cognitive abilities in particular ways, they suggest.
The team further notes that physical activity mapped onto speed reserve, even after accounting for brain hippocampal volume, total gray matter volume and white matter hyperintensities.
“These observations suggest that, in addition to physical activity preserving brain volume, physical activity may also maintain other aspects of brain health not captured by structural markers, such as functional brain networks and brain perfusion, important for processing speed,” the researchers write.
They conclude: “Overall, our findings suggest that sex and APOE4 carrier status are important factors to consider in the association between the beneficial effects of lifestyle activities on cognitive reserve.”