Physical Activity May Be Key to Cognitive Health

While brain fog is not an official medical diagnosis and there is no one definition, if you have it, you know. It can include symptoms like trouble thinking clearly, forgetting and inability to focus. And it’s linked with several different conditions, including menopause, sleep disorders, long COVID, autoimmune diseases, traumatic brain injury and hypothyroidism.

If you have brain fog and a condition related to it, treating the condition may help correct your foggy brain. But it can often take a while to find the right treatment. What if there was something you could do today to help your brain out? Turns out, there is. 

Researchers from Australia and the U.S. teamed up to investigate how exercise might influence brain health, including various aspects of cognition. Their findings were recently published in the journal Age and Ageing. Let’s break them down.

How Was This Study Conducted?

The purpose of this study was to examine how people spend their time over a 24-hour period, considering three primary lifestyle behaviors—sleeping, sedentary behavior and physical activity—and how these behaviors are linked to brain health. Physical activity was also broken down into light, moderate, vigorous and moderate-to-vigorous.  

Data was drawn from a previously conducted U.S. study called the IGNITE study—Investigating Gains in Neurocognition in an Intervention Trial of Exercise. To be included in the IGNITE study, participants needed to be between 65 and 80 years old and free of severe mental illness, neurological disorders, recent cardiovascular events, type 1 diabetes and uncontrolled or insulin-dependent type 2 diabetes. In addition, they self-reported as being inactive. 

There were 648 participants in the IGNITE study. As part of the study, each participant wore a wrist accelerometer for seven days, which recorded their activities, including sleep, and the intensity with which other activities were performed. Participants missing complete accelerometer data were disqualified from this current study, leaving 585 participants for this analysis. Those participants had an average age of 70, and 70% were female. 

Participants also performed cognitive evaluations, examining five different elements of cognition, including:

• episodic memory (the what, where and when details of an event)
• processing speed (how fast your brain thinks)
• working memory (ability to store information for short periods)
• executive function or attentional control (how well you plan, focus and multitask)
• visuospatial function (ability to recognize places and navigate through spaces)

What Did This Study Show?

After examining the data and running statistical analyses, including after adjusting for certain demographics, researchers found a clear connection between moderate-to-vigorous physical activity and several factors of cognition. Specifically, those with higher levels of moderate-to-vigorous physical activity scored higher in processing speed, executive function and working memory. And those with less moderate-to-vigorous physical activity scored lower in those same areas. 

Researchers did not find a connection between physical activity and episodic memory or visuospatial function outcomes in this analysis. 

One limitation of this study is that it is not long-term (longitudinal). It captures people’s behavior over just one week, which might not be an accurate picture of their long-term behavior. Also, as a cross-sectional study, it can only establish associations between factors; it cannot say that one causes the other. In addition, the IGNITE study, which is where the data for this study came from, did not screen for sleep disorders. So while some participants may have gotten a certain number of hours of sleep, the quality may not have been high. And we know that there is a sleep-cognition link.

How Does This Apply to Real Life?

Keeping in mind that the participants for this study were, on average, 70 years old and inactive, researchers found that those who had just 5 minutes of moderate-to-vigorous activity a day showed better cognitive skills compared to those who had just 1 minute or less of it. 

The current recommended guidelines for physical activity include at least 150 minutes of moderate physical activity or 75 minutes of vigorous physical activity per week (or some combination of the two), plus at least two days of muscle-strengthening activities. The guidelines also state that any amount of activity is better than none, and the intensity and type of activities should be based on your current fitness level and abilities.

If you’re currently inactive or hate to exercise, start by simply moving your body more often. This can look like taking more frequent breaks from your desk and walking a lap around your house or office, taking the stairs instead of the elevator and parking at the far end of the parking lot when you go shopping. 

Also, look for ways to be more intentional with your movement. For example, instead of loading up the laundry basket, take one armload of clothing at a time to put away. The same goes for bringing groceries into the house. If you have a desk job, get a standup desk and use a stability ball as your desk chair when you do sit. This makes it easy to take small breaks to do some core work throughout your day—or to simply sit on your ball and bounce away some stress.

Regardless of your physical activity status, anyone can experience temporary brain fog at certain times of the day. Change and movement are the quickest ways to banish the brain fog that can show up from sitting too long. So when you find it difficult to concentrate and focus or just feel sluggish, get up. Take some deep breaths and walk, stretch, do a mini yoga sesh or burpees—anything that changes your body’s state and gets your heart rate up a bit. 

Another area to consider is food. Be sure that you’re eating regularly and getting the nutrients you need to stay focused throughout the day. Having a meal with protein and healthy fat that can help stabilize blood sugar, which will help. Plus, whole grains and other complex carbohydrates can help you fuel your brain. Glucose is the only fuel your brain runs on. If you’re not providing it with what it needs, you’re likely to experience brain fog. 

If you want some guidance and a balanced approach to help prevent brain fog, try out our seven-day cognitive health meal plan or a 30-day MIND diet meal plan to get started. All of our meal plans are designed by registered dietitians, so they not only provide your brain and body with the nutrients they need for overall good health, but also help prevent sharp rises and sudden dips in blood sugar, which can be a contributing factor of brain fog. 

Sleep also influences how well you think, concentrate and remember. If you’re not getting enough of it—seven to nine hours a night—or it’s lacking quality due to a sleep disorder, brain fog may ensue. Get into a regular bedtime routine, dim the lights about an hour before your head hits the pillow, engage in calming activities before bedtime, get off your devices, and make sure your room is on the cooler side as far as temperature goes. If you snore or know you have obstructive sleep apnea or insomnia, see your medical practitioner for evaluation. 

Chronic stress can also bring on brain fog, as your nervous system is continually on high alert, and your brain’s attention is split between the task at hand and whatever is stressing you out. Plus, being chronically stressed also means you’ve got certain hormones that are produced at higher levels, including cortisol. And cortisol that is not properly regulated due to chronic stress has been linked with mild cognitive impairment.

The Bottom Line

This study suggests that how we spend our day may influence brain health, including brain fog. Incorporating even small amounts of exercise throughout the day can help stave off brain fog and even support your cognitive health overall, especially when it comes to executive function and processing speed. And, as Audrey Collins, Ph.D., one of the study authors, notes in a press release, it all starts with how you choose to spend your free time.

“There are only 24 hours in a day, so every day, we make decisions about how we spend our time. For example, if we sleep for eight hours, then there’s 16 hours remaining for waking behaviors like physical activity or sedentary behavior—that’s the basic reality,” says Collins.