October 23, 2012
Older People Who Exercise Have Less Brain Shrinkage
Lawrence LeBlond for redOrbit.com - Your Universe Online
Physical exercise at any age is good for the body. But those who are later in their years may have a better reason to continue exercising than worrying about their figure. According to a study published in the latest issue of the journal Neurology, researchers have found that people over 70 who remain physically active have less brain shrinkage than those who do little or no exercise.
Experts from Edinburgh University say that people who exercise in their 70s may not only be halting their brains from shrinking, but also lowering the risk of dementia. And the good news is that exercise doesn´t have to be strenuous, they noted--just going for a walk several times per week suffices.
However, the experts found no evidence that participation in social and mentally stimulating activities, such as playing a game with a friend, or doing a tricky crossword, contribute to overall brain health in older people.
“People in their seventies who participated in more physical exercise, including walking several times a week, had less brain shrinkage and other signs of aging in the brain than those who were less physically active,” said study author Alan J. Gow, PhD. “On the other hand, our study showed no real benefit to participating in mentally and socially stimulating activities on brain size, as seen on MRI scans.”
Gow and his colleagues studied brain scans over a three-year period of 638 people born before 1936. The group gave the researchers details about their exercise habits, ranging from just completing necessary household chores to keeping fit with heavy exercise and competitive sports several times per week.
Previous research has shown that exercise helps reduce the risk of dementia and can slow its onset. But scientists are still unclear why. Exercise does increase blood flow to the brain, delivering doses of oxygen and nutrients to brain cells, which could be an important factor in keeping dementia away.
Researchers are also not clear on another aspect of the study: Are people´s brains shrinking because they are not exercising, or are people less inclined to exercise due to brain shrinkage?
One thing´s for sure, exercising is an easy thing to do, and it is beneficial not just for your body, but for your mind as well.
“This study links physical exercise to fewer signs of ageing in the brain, suggesting that it may be a way of protecting our cognitive health,” noted Dr Simon Ridley, head of research at Alzheimer's Research UK. “While we can't say that exercise is the causal factor in this study, we do know that exercise in middle age can lower the risk of dementia later in life.”
“It will be important to follow these volunteers to see whether these structural features are associated with greater cognitive decline over the coming years. More research is also needed to tease out how physical activity might be having a beneficial effect,” he told BBC´s Michelle Roberts.
“This research is exciting as it provides vital clues as to what impacts the way our brain ages and how we could tackle mental decline. If we can establish definitively that exercise provides protection against mental decline, it could open the door to exercise programs tailored to the needs of people as they age,” added Professor James Goodwin, Head of Research at Age UK.
“We already know that exercise is important in reducing our risk of some illnesses that come with ageing, such as cardiovascular disease and cancer. This research reemphasizes that it really is never too late to benefit from exercise, so whether it's a brisk walk to the shops, gardening or competing in a fun run it is crucial that, those of us who can, get active as we grow older,” said Goodwin.