Here’s What Happens to Your Brain When You Exercise, According to a Neuropsychologist

We all know that exercise is the key to maintaining a healthy heart and a fierce bod…but what does it do for the mind? We dove into the scientific research and asked a neuropsychologist to explain what happens to your brain when you exercise. Here’s what we learned. (Spoiler: Bed rotting isn’t doing your brain any favors.)

Dr. Sanam Hafeez, Psy.D, is an NYC-based neuropsychologist and school psychologist. She is also the founder and director of Comprehensive Consultation Psychological Services, P.C. Hafeez graduated from Queens College, CUNY, with a BA in psychology, and then went on to earn her doctorate in Psychology at Hofstra University. Hafeez provides neuropsychological educational and developmental evaluations in her practice and also works with children and adults who suffer from PTSD, learning disabilities, autism, attention and memory problems, trauma and brain injury, abuse, childhood development and psychopathology.

Look, we get it: Your New Year’s resolution to start exercising on the reg hasn’t really panned out because, well, you’d rather just watch a movie and chill. But believe it or not, that’s not what your brain actually wants…or at least not what it needs. Read on to learn about some of the remarkable things exercise can do for your brain health.

Dr. Hafeez tells us that “physical activity stimulates the release of chemicals that dilate blood vessels, leading to increased blood flow and oxygen to the brain, which in turn promotes its health and optimal functioning.” So does this mean that a hard core spinning session will make you smarter? Your workout routine won’t turn you into Einstein overnight, but research does indeed show that it will improve your overall cognitive functioning and help ensure you’re firing on all cylinders. (More on that below.)

A run around the park won’t just create a temporary rush of blood to your head, but can actually have some pretty cool long-term benefits too. “Exercise has been shown to promote the creation of new neurons in the hippocampus, a brain region critical for learning and remembering things,” says Dr. Hafeez. In fact, this 2018 study published in Frontiers in Neuroscience posits that this hippocampal neurogenesis results not only in improved memory and learning skills, but also has neuroprotective benefits that slow cognitive decline. Specifically, the CDC says exercise can help prevent neurodegenerative diseases like dementia.

Dr. Hafeez points out that regular physical activity is also associated with improved attention, concentration and problem-solving skills. Interestingly enough, it’s not just the hippocampal areas that experience growth as a result of physical exercise. This 2018 study published in Frontiers in Psychology found that regular, moderate exercise resulted in increased gray matter in the frontal area of the brain, which is the part of the brain responsible for the aforementioned executive functioning skills.

You probably know this one already, but Dr. Hafeez confirms that “exercise stimulates the release of endorphins in the brain, which contribute to overall happiness.” Hence that blissful feeling you get immediately following a solid workout. How does this work, you ask? Well, endorphins are hormones produced by the brain to alleviate pain—and they are released during stressful and pleasurable activities alike. Once released, endorphins attach to opiate receptors in the reward center of the brain and the result is a wonderful, natural high.

In addition to endorphin release, exercise is also linked to an increase in the production and release of dopamine and serotonin—neurotransmitters that have an impact on mood regulation, social functioning and sleep, among other things. The mechanism for this isn’t entirely understood, but the effect is clear: “Exercise has been shown to be an effective method for alleviating symptoms of depression and anxiety by promoting the release of these mood-enhancing neurotransmitters,” says Dr. Hafeez.

Now that you know the impressive brain-boosting benefits of physical exercise, you might be wondering whether having a sedentary lifestyle is harmful or simply, well, neutral as far as the brain is concerned. Alas, science suggests the former. Here’s what happens to your brain when you don’t exercise.

Per Dr. Hafeez, “blood flow to the brain may decrease over time without regular exercise, which can result in reduced delivery of oxygen and nutrients to brain cells, potentially impacting their health and function.” In other words, a sedentary lifestyle effectively puts your brain on a diet it doesn’t need. Indeed, a 2021 study published in Medicine & Science in Sports & Exercise found that decreased cerebral blood flow following periods of prolonged sitting is best corrected by (you guessed it) physical activity breaks.

We mentioned that exercise results in an increase in the production and release of dopamine and serotonin, so it should come as no surprise that lack of exercise can decrease the production and release of these neurotransmitters. The consequence? Negative moods, and a higher risk of developing mental health conditions like depression and anxiety.

If you’re not exercising, you can’t benefit from that oh-so pleasant post-workout endorphin rush. Worse still, Dr. Hafeez tells us that “physical activity helps regulate stress hormones like cortisol, [which means that] stress levels may remain elevated without exercise and could lead to chronic stress and anxiety.” (If this information is stressing you out, you know what to do.)

According to Dr. Hafeez, “sedentary behavior can disrupt sleep patterns and lead to poor sleep quality, which can further exacerbate cognitive deficits and mood disturbances.” And, in case you needed more proof that a light workout a day keeps the doctor away, research shows that poor sleep quality is an independent risk factor for a whole host of other health conditions, including high blood pressure, heart disease, kidney disease, diabetes and stroke.

Regardless of how stimulating you find your desk job, there’s evidence to suggest it might actually be shrinking your brain—provided you’re sitting around during your free time, too, that is. The expert says, and this 2020 study published in the Journal of Clinical Medicine confirms, that a sedentary lifestyle may result in decreased brain volume—specifically, reduced gray matter in regions important for memory and cognition.

The picture is clear: Your brain thrives on physical activity (and your body does too). Do yourself a favor and find a workout that you actually enjoy enough to maintain…or, at the very least, try fast-walking (or actually running!) your daily errands. It’s just the smart thing to do.