You might be able to outrun your genes.

Mental performance is the key to almost everything we do. Whether we’re getting through another college semester, taking on a new project at work or managing a team through tight deadlines, we rely on mental sharpness, steady mood and sound decision-making.

As we get older, we may experience “senior moments,” but the thought that the loss of our mental acuity might accelerate is terrifying. Fortunately, there are several healthy lifestyle habits that keep us sharp and also markedly reduce our risk of developing Alzheimer’s or other forms of dementia: good sleep, aerobic exercise, healthy diet and lifelong learning.

On the Scientific American blog, author Sam Gandy cites exercise as “perhaps the single most important factor that can have an impact on late-life dementia risk.” And according to Exercise is Medicine, regular exercise can cut our risk of developing Alzheimer’s by 40 percent.

Even better, researchers note that exercise immediately improves mental performance across the board, improving reactivity, mood, alertness and judgment.


1. Exercise helps us sleep better.

The immediate effects of sleep loss are easy to spot—dark under-eye circles, extra coffee and feeling sluggish all day long. And if we average four hours of sleep a night, within five nights, we’ll become as cognitively impaired as someone who’s had too many drinks to drive.

We’ll have:

  • longer reaction times
  • poor judgment and reasoning
  • difficulties problem-solving
  • lack of attention to detail

Not exactly a recipe for success, is it?

Over the long haul, not getting enough good sleep is a risk factor for pretty much every chronic disease: diabetes, obesity, heart disease, depression and cancer, as well as Alzheimer’s and other forms of dementia.

Fortunately, regular exercise makes it easier for us to fall sleep and improves the quality of that sleep. Quality is critical because deep sleep is like a power wash for the brain, removing waste products (like Aβ) that build up over the day.

For better sleep, try to exercise every day. This can be as low-key as a 10-minute walk or your favorite group class—whatever gets you moving will help.

(And don’t stress about your timing. A 2013 National Sleep Poll found that people who exercised reported better sleep than those who didn’t—regardless of what time of day they exercised. There are more sleep tips and interesting sleep science at

2. Exercise gets our blood moving.

Have you ever felt more alert after a walk?

Aerobic exercise, like walking or cycling, increases the body’s need for oxygen. We breathe more and our heart rate increases, sending out more oxygen and nutrient-rich blood. Increased blood flow to the brain makes us feel alert and improves the speed of communication between our brain and the rest of our body. With regular exercise, we build more of the small blood vessels (capillaries) that send blood deep into the tissues, increasing overall blood flow even when we’re resting.

This has a huge long-term benefit, too. Runners who carry the Alzheimer’s risk gene APOE e4 show similar amyloid-beta profiles as non-carriers. They’re quite literally outrunning their genetic risk.

And in the case of vascular forms of dementia, aerobic exercise is prescribed as part of a treatment plan to prevent further damage to the brain’s blood vessels.

3. Exercise reinforces our “neural net.”

Neural net is the sci-fi-sounding term for the network of neurons throughout our entire brain and body.

(Side note: In their sci-fi cult classic “The Unincorporated Man” (Tor Science Fiction, 2015), authors Dani and Eytan Kollin imagine a future in which the internet not only runs on devices but also through our minds. Fittingly, they call it “the Neuro.”)

We used to believe that the adult brain was a finished product. That the only change we could make to the brain was to damage it irreparably. Neural plasticity is the name for our recently discovered ability to grow new neurons and make new connections between neurons. The more connections we make between neurons, the more ways they have to communicate.

This can protect against Alzheimer’s or other types of dementia by giving our brains detour routes for accessing information when the usual pathways are damaged.

And it helps in the short term by giving us more options for handling information and decision-making—resulting in faster, sharper thinking.

To grow new neurons and new connections, we have to learn new things and meet new challenges. We’ve all heard about the benefits of crossword puzzles and learning French, but learning new movements and physical skills counts, too.

Whether you’re learning to chop veggies like a chef, taking jujitsu for the first time or simply trying a new exercise in the gym, you’re taking advantage of neural plasticity. The key is to mix it up. Because if nothing’s changing, nothing will change.

Photo credits: Boggy, Voyagerix, gpointstudio, cloudrain, Adobe Stock