What Exercise Does To Your Brain

 We all know that exercise is good for your body and your brain. But why? In fact, exercise decreases depression and anxiety. 

How and what kind of exercise does that? 

That's what I'm talking about today. I'm um, Dr. Tracy Marks, a psychiatrist and I make mental health education videos. You've probably heard the term runners high which describes a phenomenon where after intense aerobic exercise, like running, you can experience this euphoric feeling and sense of well-being. For years it was hypothesized that this was due to the release of endorphins which is your body's natural opiate. Well, it turns out the runner's high really isn't that common among runners. But anyone can experience a relaxed feeling after moderately intense exercise, not from endorphins, but from endocannabinoids. Let me explain.

 You do get endorphin release with exercise that serves the purpose of lessening pain perception during and after intense activity. But those endorphins don't affect your brain and therefore your mood because they don't make it across the blood-brain barrier. Your brain is very selective about what it allows to pass through the gate. Some molecules can pass and then others not. An example of this is with antihistamine medications.

 Histamine is a chemical in your brain that makes you alert and medications that block it make you sleepy. Histamine in your body from the neck down causes the allergic response of itching hives airway constriction. So below the neck antihistamines block this allergic reaction. Some antihistamines like Benadryl make you sleepy because they cross the blood-brain barrier and affect the histamine receptors in your brain. Antihistamines that don't make you sleepy, like Zertech, were manufactured to be able to not make it to the brain. So back to exercise. 

We now believe that the good feeling you get after exercise is due to the release of endocannabinoids that do cross the blood-brain barrier. Endocannabinoids are substances that your body produces that activate cannabinoid receptors in your body. The two most studied endocannabinoids are AEA and two AG. I'll spare you the full names but the A stands for arachidonic acid. When something is made in the body it's called an endogenous source. When the source is outside of your body it's called exogenous. The two most studied exogenous cannabinoids are THC and CBD from the cannabis plant. Cannabis has over 100 cannabinoids that affect the cannabinoid receptors in your body. But THC and CBD are the two that we know the most about.

 So you can think of vigorous exercise as making your own strain of cannabis. Sort of. Your homemade cannabinoids have a mood-lifting and anxiety-reducing effect, but it get better. Regular exercise has a longer effect on improving mood and anxiety because it triggers brain-derived neurotropic factor which causes neurogenesis. Neurogenesis is the growth of new cells and the regeneration of damaged cells. Also, researchers have seen that people who exercise regularly have bigger hippocampi because of this neurogenesis. In the brain world, you want to have a big hippocampus. A small hippocampus is considered a hallmark of depression. 

Your hippocampus is located in your temporal lobe, and it's associated with memory and learning. It not only controls learning tasks like problem-solving but controls your ability to process emotion and allows you to level up your psychological insight. Researchers also believe with neurogenesis, that there's a downstream effect of increasing dopamine and serotonin, both of which we know to improve mood. What kind of exercise can give you this nice big hippocampus? The Centers for Disease Control and Prevention and other sources recommend 150 minutes a week of moderate-intensity exercise or 75 minutes a week of vigorous intensity. 

With moderate intensity, you can talk, but not very easily, and you can't sing because your breathing is too fast to hold notes. So if you're talking, you're huffing. Examples of moderate exercise are brisk walking around 3 mph, slow biking, dancing, or doubles tennis. So if you're walking your dog or gardening and you can sing or whistle a tune, you're not doing it hard enough. With vigorous intensity, you can't talk because you're breathing too hard. Examples of this are running jogging at around 6 mph, which would be a ten-minute mile swimming laps, or some aerobic classes, depending on how hard they have you working. 

You can divide up these times however you want, but it's best to spread it out over the week, like 30 minutes on a treadmill five times a week for moderate exercise, or a 15-minute fast bike ride five times a week. Now, I will say any kind of activity is better than no activity, so a slow walk in your neighborhood still brings you some benefits. But to activate the endocannabinoid system and increase neurogenesis, you need some phobic activity.

 I have a link in the description that will give you more guidelines on physical activity. It's from the Department of Health and Human Services. If you like this video, take a look at this one on how intermittent fasting also changes your brain wiring. Thanks for reading

 WATCH HERE>>

What Exercise Does To Your Brain