I have written a lot about the topic of Alzheimer's disease. This is a life-changing chronic condition, not only for the individuals whose brains are afflicted by the disease, but for their loved ones as well. It is life-changing every way one can imagine: mentally, physically, emotionally, socially and financially.

It also currently has no cure.

As such, it is a topic of focus for me as a practioner and researcher of all things preventive. We all spend a lot of time planning our financial retirement but not nearly as much planning for our health in retirement.

This "health planning" can be constructed very similarly to how we plan for our financial security in our later years: By making proactive changes to what we do today, in hopes that we shall reap the benefits years down the road.

And it may be easier than one may think.

Take exercise: What we know is we should be fitting into our daily routines for a whole host of other reasons can benefit us in the quest for prevention of Alzheimer's as well. We are seeing more and more evidence that the lifestyle choices we make, day-in and day-out, have a large effect on numerous chronic diseases. Alzheimer's is no exception.

Research has shown us that physical activity is associated with lower rates of cognitive impairment in older adults. Two new studies again support the practice of regular physical activity to ward off cognitive decline in our later years. These studies were published Online First by the Archives of Internal Medicine to coincide with a presentation at the International Conference on Alzheimer's Disease in Paris.

In one study, French researchers examined data from the Women's Antioxidant Cardiovascular Study. This included women who had vascular disease or three or more risk factors. The researchers established the women's baseline physical activity levels and measured them again every two years thereafter. Years later, they conducted telephone interviews to assess cognitive function.

The researchers found that as the women's activity levels increased, the rate of cognitive decline decreased. And it didn't take much: One brisk, 30-minute walk a day was the level of activity associated with lower risk of cognitive impairment.

In the second study, Canadian researchers utilized data from the Health, Aging, and Body Composition study. The researchers got super-scientific to obtain more accurate measurement of activity levels. They used specially labeled water and analyzed blood and urine tests to measure activity, and gave the participants cognitive tests over the following years. They found that participants who had the highest activity energy expenditures scores tended to have less cognitive impairment. They also observed a significant "dose response" between activity and cognitive impairment: more activity, less dementia.

In a commentary accompanying the articles, Eric B. Larson, M.D., M.P.H., wrote: "I believe that these findings can inform practice and the advice that we give our aging patients. We can tell them that ongoing maintenance of physical activity is definitely worthwhile and likely of increasing benefit as they advance into old age."