Every day we learn more about the brain, and how to preserve its health over the years. One thing I can say with confidence based on my research is that cognitive decline is not inevitable. Lifestyle matters, and science has shown that one of the best ways to keep your brain performing well is to engage in regular exercise.
A review of the best available evidence on dementia, recently published in The Lancet, concluded that a full 1 out of every 3 dementia cases may be preventable by making the right lifestyle choices, including eating right, smoking less, and moving more. Exercise is one of the best places to start when reexamining your lifestyle with the goal of maintaining brain health.
Some people have all the signs of dementia, with damage and other signs of trouble showing up in their brain scans, yet their cognitive performance remains unaffected. This has led to the theory of cognitive reserve. The idea is that healthy older people don’t necessarily avoid the effects of aging, but they are able to continue functioning normally because they have brain power to spare. They have a “reserve” of cognitive resources to draw on when damage occurs.
Research is showing that lifestyle choices made earlier in life affect how much cognitive reserve is available later in life. The review above, as well as another recent study of over 2000 older adults, have confirmed that physical activity is one of the top predictors of cognitive reserve. People who are physically active not only push through physical limits, but keep on going when age would otherwise devastate their ability to think. It’s like putting more gas in your tank, so that even if some gets used up, you have more to spare.
A key point is that this is a protective effect, rather than a treatment. The best time to begin exercising is before signs of dementia set in. Building up that cognitive reserve takes time, and to continue the metaphor above, once the low gas light has been on for a while, it may be too late to get to the next gas station.
That being said, whether you’re 28 or 82, you will benefit from exercising more, and have a better chance at cognitive health in future years. The best time to start is now.
Increased cognitive reserve isn’t the only way that exercise prevents brain aging. Here is a figure from the Lancet paper mentioned above, which summarizes strategies for preventing dementia that have been proven to work:
As discussed, increased cognitive reserve (the blue circle) is one front in the war on cognitive decline, and can be improved with strategies like education and exercise. Reduced brain damage (the orange circle), another front, can be improved with strategies like reduced smoking, as well as exercise. Reduce inflammation (the green circle) benefits from certain drugs, and … you guessed it, exercise.
Exercise attacks cognitive decline from all three angles.
Another often-forgotten benefit of exercise is that it tends to naturally bring along other healthy brain habits. Getting out of the house to exercise can lead to interacting with people and expanding your social network. Some types of exercise, such as sports, group fitness, and dance classes require cognitive effort alongside physical effort. And of course, exercise is a part of reducing obesity. All of these are additional lifestyle factors known to slow cognitive decline.
The implication of the information above is that the best exercise program to prevent cognitive decline is a rich, multifaceted, and even fun set of activities. One of the key messages coming out of recent scientific research is that dementia prevention should be tailored to unique individuals, integrating with your own medical, social, and cultural needs and preferences.
Any exercise is better than none, but a program that will tackle brain health in addition to physical health should be based on cognitive outcomes, and customized. That means tracking your physical and cognitive outcomes over time, and engaging in a mix of different activities so you can find the activities that work best for you. A personalized fitness plan that includes cognitive testing to measure outcomes will be most likely to boost cognitive reserve, and stop decline in its tracks.
Exercise is not the only route to healthy aging, but it is one of the most well-established. The right physical activity routine, implemented as early as possible, can make the difference between living with cognitive decline and staying sharp well into old age.
Join Dr. Adrian Owen for a webinar on January 25, 2018 at 12 noon. He’ll cover the lessons learned through 30 years of research on the brain. His research combines neuroimaging (MRI and EEG), with cognitive studies in brain-injured patients and healthy participants. The live webinar will focus on how he tests cognition and memory to the latest science regarding what affects the brain. Find out about the impact of sleep, fitness, brain exercises, music and nutrition on one of our most mysterious organs. Register here
Dr. Owen has spent the last 20 years pioneering breakthroughs in cognitive neuroscience. His work has been published in prestigious journals such as The Lancet, Nature, Science and The New England Journal of Medicine.
Before assuming his Canada Excellence Research Chair at Western University, Dr. Owen was a senior scientist and assistant director of the Medical Research Council’s Cognition and Brain Sciences Unit in Cambridge, United Kingdom. His work there, and at the Wolfson Brain Imaging Centre at the University of Cambridge, used functional neuroimaging to explore attention, memory and control in brain-injured and healthy volunteers.
He revolutionized the assessment of brain function by harnessing the power of computerized cognitive testing, and is now the chief scientific officer at Cambridge Brain Sciences—a platform for tracking and optimizing cognitive performance.
Into the Gray Zone documents Owen’s ongoing quest to understand the relationship between brain, mind, and consciousness.