Exercise and Dementia

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This article was edited and updated on December 8, 2021.

What is dementia?

Dementia is not a single condition; the word describes a group of symptoms which affect our thinking and social abilities severely enough to interfere with daily functioning. Memory loss is common, and Alzheimer's disease is the most common cause of progressive dementia.

Memory loss alone doesn't mean you have dementia; everyone knows that, as we age, we have lapses in our memory. Dementia, however, indicates problems with at least two brain functions — (1) memory loss and impaired judgment or language, and (2) the inability to perform daily activities. 2 A person with dementia may be confused, unable to remember people or their names, may demonstrate personality changes, and may feel as though they are in a maze and don't know how to get out.

However, some causes of dementia are treatable and even reversible.

Can exercise prevent dementia?

We know that the brain normally shrinks with age. The brain's memory hub — the hippocampus — is particularly vulnerable if a person already has the genetic risk for the disease. This gene is called APOE-e4 3.

Recent research has found that regular exercise may keep Alzheimer’s at bay. "One study of men and women in their 60s, 70s and 80s found that being active at least three times a week stopped the brain from shrinking. And the even better news is that even those with that common gene were protected by brisk walking, jogging, swimming and cycling."

Kirk Erickson, an expert in the study of the aging brains, said: "This is the first study to look at how physical activity might impact the loss of hippocampal volume in people at genetic risk for Alzheimer’s disease. There are no other treatments shown to preserve hippocampal volume in those that may develop Alzheimer’s disease. This study has tremendous implications for how we might intervene, prior to the development of any dementia symptoms, in older adults who are at increased genetic risk for Alzheimer’s disease." [My italics.]

What do we already know about the brain?

We are still learning much about the complexities of the human brain. It's possible — according to one study — that exercise may be one of the factors that decides if a brain is able to overcome its genetic inheritance.

In another study, US researchers found that even those with the genetic predisposition for Alzheimers were protected by "brisk walking, jogging, swimming and cycling." The study concluded: "The only brain shrinkage occurred in those with the gene who did little or no exercise."

Researcher Dr. J. Carson Smith, of the University of Maryland, said: "We found that physical activity has the potential to preserve the volume of the hippocampus in those with increased risk for Alzheimer’s disease, which means we can possibly delay cognitive decline and the onset of dementia symptoms in these individuals. Physical activity interventions may be especially potent and important for this group."

As with all health conditions, future research is needed "to work out how exercise and genetics interact to lower the risk of Alzheimer’s. And that more evidence could lead to those with a family history of the disease being ‘prescribed’ exercise."

Dr Smith ended by saying: "We do not yet have the level of exercise needed to justify this approach specifically for Alzheimer’s prevention but exercise certainly cannot harm, so should be prescribed regardless."

To read more about this research, link to this article from The Daily Mail Online.

This article is part of a series about various health conditions and the benefits of exercise. The other articles are:

I am a BCRPA-certified fitness instructor in Vancouver, BC. I teach four classes at the West End Community Centre in Vancouver, BC, mostly designed for the older adult. The Inevitable Disclaimer: Everything published here expresses only my opinion, based on my training and research. What you do with the information is entirely your own responsibility. I am not liable for any injury you suffer that seems to be related to anything you read here. Always consult your doctor before beginning an exercise program. For other articles, return to the table of contents.

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  1. These three dots behave exactly like a footnote. Click on them and you will get more information about the topic. ↩︎

  2. Such as paying bills or becoming lost. ↩︎

  3. The APOE-e4 gene is carried by up to 30 per cent of the population. It increases the risk of Alzheimer’s in old age but not everyone with the suspect DNA will develop the disease. ↩︎