October 24, 2012
A sad reality of Alzheimer’s disease is that we currently do not have a way to prevent it. We know that some people are biologically or genetically at a greater risk than others, but researchers want to find out how people can fight it off or, at the least, delay it.
Past researchers has shown that the strongest evidence for a lifestyle choice associated with Alzheimer’s prevention is incorporating exercise. A new study published in the journal, Neurology, supports this past finding that working out is more effective at protecting the brain then doing cognitive challenges such as games or puzzles.
The researchers conducted a study that included nearly 700 participants from Scotland that were all born in 1936. The participants reported their leisure and physical activity levels at age 70. They rated their physical activity on a scale that ranged from “moving only in connection with necessary (household) chores” to “keep-fit/heavy exercise or competitive sport several times per week.” They were also asked to rate how often they took part in social and intellectual activities.
At age 73 the researchers used magnetic resonance imaging (MRI) to measure certain biomarkers in the brains of the participants. The study findings appear to show that people who participated in more physical activity typically showed less brain shrinkage and fewer white matter lesions, both of which can be indicators of Alzheimer’s. Grey matter is made up mostly of nerve cells, neurons, and is primarily associated with processing and cognition, according to the Alzheimer’s Association. Alternately, white matter is composed mainly of nerve fibers, and coordinates the communication between various brain regions.
The researchers that conducted the study found that intellectual and social engagement were not as beneficial to the brain, but they did show some signs that they might also carry benefits. According to Heather Snyder, senior associate director for medical and scientific relations at the Alzheimer’s Association (but was not involved in the study), she is not surprised by the results. Physical activity is linked to promoting a healthy heart and the well-being of the brain and the heart are linked. An unhealthy heart is not as efficient at pumping the blood the brain needs.
"In terms of the exact mechanism, there's a lot that we don't know," she said.
Snyder also said that the strongest evidence from research suggests that exercise helps to prevent Alzheimer’s later in life, but cognitive exercises do not hurt. Snyder also said that researchers aren’t sure as to how much exercise is beneficial or whether it is too late to increase activity after a certain age.
One of the small studies presented showed that women between the ages of ages of 70-80 benefited from walking, balance exercises and weight-lifting. Those who did weight-lifting showed the most improvement. The researchers also found that people who began with the highest baseline benefited the most form exercise.