Engaging in regular exercise can protect against dementia by slowing down its onset, researchers reveal.
This occurrence was mainly because moderate physical activity helped improve size of certain parts of the brain that normally shrink as one gets older, like the prefrontal cortex regions and hippocampus, The Independent reported.
The study included 120 people, aged between 55 and 80. During the one year study period, participants were asked to go for 40-minute brisk walk thrice a week. During the same period, another group of the same age was assigned to simple stretching tasks.
While monitoring their brain regions after 12 months, researchers couldn't find any signs of cognitive decline associated with ageing. On the other hand, to their surprise they found that important regions in the brain including hippocampus had grown by 2 percent, Daily Mail reported. However, the same brain regions shrunk by 1.5 percent in the stretching task group.
Brain shrinkage and cognitive decline have long been known to cause brain disorders, including Alzheimer's disease and dementia. "Both of these regions deteriorate and shrink as we get older. The prefrontal cortex is really involved in a lot of higher level cognitive functions and the hippocampus is well known to be involved in memory formation, and when it shrinks it leads to Alzheimer's disease and dementia," Kirk Erickson of the University of Pittsburgh in Pennsylvania, told The Independent.
Additionally, people who exercised scored high in tasks related to memory, language and attention.
"The results suggest that brain and cognitive function of the older adults remain plastic and highly malleable. There is not this inevitable decline that we used to think there was. We can improve brain function by relatively modest amounts of physical activity," Kirk Erickson of the University of Pittsburgh in Pennsylvania, told The Independent. "With modest amounts of exercise we are able to increase the size of these structures that typically deteriorate and precede the cognitive complaints that often come in late adulthood," he added.
"The hippocampus increased by about 2 per cent over a one year period. That may sound like a modest amount but that's actually like reversing the age clock by about one to two years."
Erickson presented the study during the annual conference of the American Association for the Advancement of Science, in Chicago.
Similarly, in December last year a team of researchers from the Cardiff University in UK found that leading a healthy lifestyle - exercising regularly, following a healthy diet, abstaining completely from smoking, restricting consumption of alcohol and maintaining a healthy weight - lowered risk of developing dementia.
Apart from that, previous research has also shown that engaging in brain-stimulating activities like reading or writing throughout life also helped protect against the brain disorder.