Our previous post reviewed a study on dementia that seemed to conclude that exercise cannot improve the symptoms of the disease. Today, as promised, we’re reviewing a much larger meta-analysis study that concludes the opposite.
What Is a Meta-Analysis?
We get it! Studies seem to contradict each other all the time, and this can be very confusing to people who are just trying to get the real scoop so they can make an informed decision. Scientists aren’t blind to this problem, and one way they have attempted to enhance the accuracy of results is by creating the meta-analysis. This method extrapolates the data from many studies and then reassembles all of the subjects into one or more large groups to create one massive study.
The general idea of a meta-analysis is that the higher the numbers, the more valid the data. In other words, there’s greater power in the numbers. Therefore, comparing large groups to large groups should provide more accurate results than a small study comparing smaller groups. So this is the type of study we are featuring today.
Defining Dementia
Alzheimer’s dementia, vascular dementia, and dementia with Lewy bodies (DLB) are just a few of the many types of dementia, a degenerative brain disease that progresses and worsens slowly and is irreversible. With dementia, the neurons (cells in the brain) deteriorate or die. Cognitive impairment, which includes trouble remembering things or processing information or thoughts, is typically the first early warning sign of dementia.
It’s important to note that while dementia does cause cognitive impairment, “cognitive impairment” can also exist without dementia. For example a stroke or some other type of injury to the brain or certain medications, even, can also cause cognitive impairment. That being said, cognitive impairment, even when it’s mild, is associated with a greater risk of dementia later.
Also, cognitive impairments due to a medication or some other temporary situation will subside, while those due to dementia will progress, or slowly worsen. As mentioned dementia is an irreversible degenerative disease; however, one study suggests exercise, while it can’t reverse the disease, may be able to improve some cognitive performance. Let’s review.
Exercise Found to Improve Cognitive Impairment
The dementia study we reviewed in our last post found that while exercise improved fitness levels, it couldn’t improve cognitive function. However, another recent study, a much larger meta-analysis, provides an opposite conclusion. This meta-analysis consisted of an aggregate of 98 separate studies. The subjects were all elderly and comparisons were made between those who had cognitive impairment and those who did not. In this case, both groups participated in 52 hours of exercise, including strength training and aerobic activities. Both groups were found to have improvements in cognitive performance, such as the speed of processing thoughts and executive functions (e.g., judgment, planning, execution of plans toward goals, etc.).
So which study should you trust? The results of a meta-analysis, in science circles, are always more highly valued and trusted than a single study. So we would be more likely to hang our hat on this one. But regardless of whether or not dementia is improved, dementia patients can still benefit from the positive physical effects of exercise. So the question is, To exercise or not to exercise? In most any case, our answer is always a resounding yes to exercise!