Did you know that over 320,000 Australians are living with dementia. Unless there’s a medical breakthrough, that number’s expected to increase to 900,000 by 2050. About 1 in 10 people over the age of 65 have dementia, and another 1 in 5 have mild cognitive impairment and are at significantly increased risk of progressing to dementia.
Whilst there’s no cure for dementia, there are things you can do today, to reduce your risk. In fact about 50% of Alzheimer’s cases can be attributed to risk factors you can change.
About 13% of Alzheimer’s cases worldwide (that’s over 4 million people) can be attributed to lack of physical activity. In the USA that figure sits at 21% of cases – that’s over one fifth of Alzheimer’s cases in the US can be attributed to physical inactivity, and the figure for Australia is likely to be similar, given our modern lifestyle means we’re less active that we should be. So that means, by 2050, there will be 180,000 people with Alzheimer’s disease, who could have avoided developing it, simply by doing some regular exercise.
How does physical activity affect the brain?
This is an area which scientists are still learning about. What they do know is that:
- The brain grows new cells and connections between those new cells throughout our life, referred to as brain plasticity.
- The brain needs a good blood supply to provide it with enough with oxygen and nutrients to function well.
- Physical activity supports both these important aspects of brain biology.
Brain imaging has shown that people doing regular exercise of moderate intensity, have increased brain volume in regions important for memory, learning, concentration and planning, over people who are inactive.
They also have increased connectivity between brain regions, and they have better cognitive function.
And listen to this– oldies who are physically active have brain volumes and connectivity typical of younger adults. It is normal for the brain to shrink a little as we grow older, but this age-related shrinkage is reduced in people who do regular physical activity.
For healthy brain function, the blood vessels in the brain need to be healthy. Conditions such as diabetes, high blood pressure, high cholesterol and obesity can damage blood vessels and lead to vascular disease in the brain, which is a big contributor to dementia. Physical activity helps to keep all blood vessels healthy, not just those in the brain, and it aids in the growth of new blood vessels.
The positive impact physical activity has on the brain can be seen both over the long term and the short term.
It seems that physical activity not only reduces your risk of Alzheimer’s disease, but it also plays a role in reducing the brain damage in those who are living with the disease. People with Alzheimer’s have deposits of a protein called Amyloid on their brain. In older adults who are physically active, there are less of the amyloid changes associated with Alzheimer’s.
Some studies have investigated what happens when inactive people start exercising, and show that after 6 to 12 months of exercising, brain volume increases and cognitive function improves.
These effects have been shown across the age spectrum, including in children, so no matter what your age, exercising has the potential to improve the health and therefore the functioning of your brain.
So that’s just one more reason to get physically active now, and stay physically active. Your “golden years” can be amazing or you can run the risk of them being agonising for you and your family. You owe it to yourself to act now.