Written by Siobhan M. White & Thomas R. Wójcicki
Aging is associated with declines in cognitive function and structural changes in the brain which result in:
- Reduced efficiency of mental processes such as learning, planning, making decisions and paying attention;
- Decreased reaction time and memory impairment; and
- Decreased number of brain cells and volume.
In general, there is a commonly held belief that the aging process is inherently associated with a natural, seemingly unavoidable, deterioration of brain function.
However, emerging research in the fields of neuroscience and kinesiology suggest that many of these age-related declines in cognitive functioning are not inevitable and that help may literally be just a few steps away. Most people recognize that physical activity is essential for improving and maintaining physical health and condition. What may be less widely understood, however, is the fact that regular physical activity also positively influences cognitive health. Over the past decade, a growing body of research suggests that physical activity participation is beneficial for preserving–even enhancing–cognitive function, especially in the aging population.
Influences of physical activity on cognitive health
Engagement in regular, systematic physical activity has been shown to offer numerous benefits for certain aspects of cognitive health. For instance, older adults who are more physically active have higher mental processing speed and are better at planning, scheduling and multi-tasking. Additionally, physically active individuals are better able to focus their attention on relevant environmental cues, which may be particularly important when performing everyday tasks such as driving. Older adults who regularly exercise have also been shown to exhibit improvements in memory. Furthermore, older adults who are active are less likely to experience dementia and Alzheimer’s disease even if they carry the genes that predispose them to such conditions.
In addition to the benefits of mental processes, physical activity has also been shown to positively influence brain structure. Recent evidence suggests that participation in regular physical activity by older adults can actually result in the generation of new brain cells. Moreover, increased physical activity levels can result in the formation of new connections between brain cells, allowing the brain to work more efficiently.
How does physical activity influence cognitive functioning?
Increases in physical activity may result in an increased ability for the body to supply blood to the brain. Additionally, it may increase the levels or binding of chemicals in the brain that are necessary to perform many of the mental processes described above. The old adage “use it or lose it” may be in full effect when it comes to the relationship between physical activity and cognitive functioning. Simply learning new tasks such as dance steps or resistance exercises, for instance, may translate to improvements in mental processes that are used in everyday life.
How much physical activity is needed to reap these benefits?
Most studies done to date have shown that 45 minutes of brisk walking three times a week can be enough physical activity to result in positive improvements in brain structure and function. Combining brisk walking with strength training activities, such as weight lifting, two to three times a week may result in further improvements to cognitive health.
How do I become physically active?
It is never too late to begin a physical activity routine, as older adults who were relatively inactive have been shown to experience cognitive benefits after just 6 to 12 months of regular activity. If you are just starting out, however, it is important to start slowly. It is important that you listen to your body, use proper form and progress at a level that is somewhat challenging, yet attainable. For example, you might want to begin with a ten-minute walk, three times a week. Then you can add an additional five minutes each week until you are walking the full 45 minutes. If the weather is an issue, you may want to consider using a treadmill, an indoor track or even a local shopping mall. Explore your options. For instance, many park districts and gyms offer classes specifically designed for older adults. If you want to workout at home, perhaps purchasing an exercise video may be the answer for you.
Regardless of the option you chose, it is important to stay committed by scheduling time in your day to make physical activity a priority. Set exercise-related goals and regularly assess your progress to keep you motivated and focused. Additionally, finding a friend or significant other to exercise with may be helpful, as you can share your experiences and hold each other accountable. Every little bit of physical activity is beneficial, so even if you don’t have 45 minutes, simply dedicating whatever time you have available to physical activity can help preserve, even improve, your cognitive health.
Editor’s note: ACSM’s Position Stand on Exercise and Physical Activity for Older Adults cites extensive evidence for claims of the health benefits of exercise in this population.
View the full fall 2010 issue of the ACSM Fit Society® Page online.