January 9, 2013

Exercise Grows Brain, Reduces Alzheimer's Risk


In its short life, this blog has developed several themes. Among them: 
  1. Exercise really matters, and 
  2. I fear Alzheimer’s. 
Now, a recent article in Alzheimer’s Weekly reports on a study that demonstrates how I might use theme #1 to address theme #2. The story’s title: “Energetic Lifestyle Builds Brains by 5%.”

Using 20 years of data about 876 adults (whose cognition ranged from normal to impaired) with an average age now of 78, researchers at UCLA learned that active people create – build – 5% more gray matter in their brains. Here’s the important part: that additional size and activity helped prevent the dementia of Alzheimer’s.

That data had already been collected as part of the Cardiovascular Health Study. It included people from four different locations across the country, and provided information about body mass index and lifestyle habits.

The lifestyle factors the team measured included recreational sports, gardening and yard work, bicycling, dancing and riding an exercise cycle. The specificity of the assembled statistics allowed researchers to estimate energy output in weekly kilocalories.

Using magnetic resonance imaging (MRI) and a procedure called voxel-based morphometry, the UCLA team was able to model the relationships between energy expenditure and volume of gray matter. Explained team leader Dr. Cyrus Raji:
Voxel-based morphometry is an advanced method that allows a computer to analyze an MR image and build a mathematical model that helps us to understand the relationship between active lifestyle and gray matter volume. Gray matter volume is a key marker of brain health. Larger gray matter volume means a healthier brain. Shrinking volume is seen in Alzheimer's disease. 
Before drawing conclusions, Raji’s team established controls for age, head size, cognitive impairment, gender, body mass index, education, study site location and white matter disease. Then, what they found was a clear connection between energy output and “gray matter volumes” in parts of the brain critical to cognitive function -- the frontal, temporal and parietal lobes, including the hippocampus, posterior cingulate and basal ganglia.

Raji made another observation, which made me think I should keep walking, gardening, and riding my stationary bike… boring as that last option is for me: "What struck me most about the study results is that it is not one but a combination of lifestyle choices and activities that benefit the brain."

The bottom line: exercise improves vascular health. Aerobic activity stimulates cerebral blood flow and, as a consequence, strengthens neural connections.

Dr. Raji wisely added the standard caveat: "Additional work needs to be done. However, our initial results show that brain aging can be alleviated through an active lifestyle."

/////////////////////// 

I’ve written often about the benefits of exercise. For links to earlier posts, just type “exercise” into the search bar at right.


No comments:

UA-20519487-1