Your brain is truly amazing! With a staggering 100 billion interconnected neurons, your brain not only controls your body, but every sensation, thought, emotion and memory that you have, including your very consciousness.
Obviously, brain health is just as important as physical health. After all, it’s what makes you – well, you! A healthy brain allows you to make the most out of life.
But what can you do to keep your brain in tip-top shape?
In this article, I will show that a key to keeping your brain healthy, both now and as you age, is through physical exercise.
Talk about killing two birds with one stone!
I am mainly talking about cardio exercise, exercise that gets your heart pumping. As a rule of thumb, remember that for all things including diet and exercise — Heart Health = Brain Health!
To keep the body in good health is a duty… otherwise we shall not be able to keep our mind strong and clear.
What is Brain Health?
Brain health is keeping the functions of the brain working correctly and efficiently. Let’s look at the main functions of the brain.
Logical Reasoning: thinking in a logical way, resolving problems, forming conclusions given a set of data, performing judgements, and solving mysteries.
Attention: the ability to focus on important information. Just as important, the brain also inhibits information not needed for the current focus. Without attention the brain would wander aimlessly and not be productive.
Memory: the ability to store and recall events in the past. This includes short term and long term memories. It is key for learning, and crucial for our existence as a thinking being.
Emotions: a way the brain summarizes things through feelings, given all it’s information. Fear and disgust for example causes you to avoid things that can be bad for you. Positive emotions like happiness and joy indicates you are on the right track. Emotions are needed for decision making as well as for motivation and guidance.
Executive Function: the ability to use your various cognitive processes in a coordinated way to direct action and accomplish a goal. This including planning, breaking things down into steps, and executing them — consulting your feelings, and adjusting approach and behavior as needed. This could range from cooking a meal, to starting a company.
Creativity : involves taking information from current reality, memory and general thinking, and come up with images and ideas that do not actually exist in real life (yet!).This could be it a new invention, a work of art, or just a unique way of dealing with a certain situation.
Communication : The brain has advanced capabilities to produce and understand languages, integrating the sensory inputs with thoughts.
Well Being / Positive Mood : Mood is similar to emotion but more generalized. It integrates emotions and other cognitive and physical input and produces a general good or bad feeling based on various factors. Pleasure and overall good feeling is a powerful motivator for the brain.
Control of the Body : The brain controls the rest of the body through its output, and also gets input from the various body senses for processing. It controls both voluntary and involuntary actions, as well as advanced processing such as coordination of various parts to carry out actions (e.g., walking, bicycling, karate, etc)
What If Our Brain is Not Healthy?
We take brain health for granted –until it shows signs of failure. This can range from subtle flaws to serious mental conditions. When your brain is not healthy you can experience the below:
- have problems remembering things well
- trouble learning or concentrating
- have brain fog, cannot thinking clearly
- experience excessive stress or anxiety
- have problems getting anything done
- feel depressed, or have a persistent low mood
Also, there are diseases such as Alzheimer, Autism, Parkinsons, Schizophrenia and Major Depression.
A Quick Tour of the Brain
Before we show how exercise improves the brain, let’s take a quick look around it. The brain is made of many different parts with different roles, combining to make up your being. Let’s look at four main parts of the brain: brain stem, cerebellum, limbic system, and cerebrum.
The brain stem is located at the base of the brain, connecting it to the rest of the body through the spinal cord. It controls automatic functions like breathing, heart beats, digestion and swallowing. It’s the first receiver of sensory data like pain and touch.
The cerebellum controls your coordination, balance, posture and general timing of movements. It’s also involved in motor learning.
The limbic system is where your emotions occur and where learning and memory are processed. Inside the limbic system is the hipothalamus that controls primal feelings like hunger and thirst. Also in the limbic system is the amygdala which is the seat of our emotions. Another key part of the limbic system is the hippocampus, which is what controls learning and processes and creates memories for long term storage.
The cerebrum is where your higher level reasoning, problem solving and general stream of thought occurs. This is the bulk of our brain and is what differentiates us from other animals. The cerebrum has an intricate layer of gray matter on its surface known as the cerebral cortex, which in turn is divided into the following:
- Frontal Lobe – controls creative and abstract thinking, problem solving and attention..
- Parietal Lobe – controls your feeling pain and processing the feeling of touch
- Occipital Lobe – processes all the information from your eye as well as controls facial expressions and language processing
- Temporal Lobe – forms short term memories, processes audio from the ear, helps in understanding speech
What Makes the Brain Work?
The brain processes information using advanced nerve cells called neurons. These cells are arranged in intricate patterns to coordinate the flow of thoughts and other activities of the brain.
Neurons receive inputs, which are processed to decide whether the neuron will “fire” or not. If it does fire, it outputs that state to all neurons connected to its outputs.
You can think of the neuron firing like a “bit” of information in a computer, whose value can be off (0) or on (1), although as you will see it’s somewhat more complex than that.
Neurons receive input from your senses, and ultimately sends signals to control your muscles. By far though, neurons mostly communicate with other neurons, forming a massive neural computer-like network.
Each neuron connects to around 100,000 other neurons. Given that the total number of neurons in the brain is 100 billion — that’s a lot of connections!
How do Neurons Convey Information?
Neurons receive input from thousands of other neurons via fibers known as dendrites (reference the figure above). A neuron determines if it should “fire” or not based on these inputs. If the neuron fires, it sends an electrical signal through the axon to the axon terminals. These axon terminals are connected to thousands of other neuron’s dendrites via what is known as a synaptic gap.
Communication by Chemical
Neurons communicate with each other through this synaptic gap via chemicals known as neurotransmitters. The neuron’s axon terminals release neurotransmitters when the neuron fires.
Once the chemicals are released, they cross the synaptic gap and are received by receptors of the neuron on the other side to complete the communication. Some neurotransmitters don’t make it to the other side of the gap and are diffused into the surrounding tissue fluid.
To Fire or Not Fire
An interesting thing about neurotransmitters is that they can be either excitatory or inhibitory. This means that if a neuron gets an excitatory neurotransmitter on its input dendrite, it makes that neuron more likely to fire. If the neuron receives neurotransmitters that are inhibitory however, it actually makes the neuron less likely to fire.
Choosing to fire or not fire are equally important. It’s important obviously to convey brain information since you cannot picture a computer using all 1’s or all 0’s. But it’s also more complex than that in that overall neurons can be encouraged to not fire for a calming effect on the brain — and that is what inhibitory neurotransmitters do.
Inhibitory neurotransmitters helps put on the brakes in mental activity, and are associated with calm and relaxation.
Excitatory neurotransmitters on the other hand encourage brain activity, and are associated with alertness, and energy. It’s important to keep both of these neurotransmitter types in proper balance.
How Exercise Helps the Brain
Physical exercise has been shown to help the brain in a variety of ways. Let’s take a look at seven main ways.
1. Increases Cerebral Blood Flow
The brain needs a good supply of blood to function properly. In addition to removing wastes from the brain, blood also supplies much needed glucose and oxygen to it. In fact the brain consumes half the glucose in the body and one fifth of the oxygen. Your brain cannot survive long without blood. Just a few minutes without it will kill brain cells and result in a stroke.
But even just poor brain circulation can hamper energy production in the brain, and cause brain fog or poor cognitive functions, according to numerous studies.
Also according to this Rotterdam study, low blood flow makes it more likely to develop cognitive decline and is associated with dementia. It has also been linked to Depression and Parkinson’s disease (References Depression study, Parkinson disease study).
There are ways to improve your blood circulation to the brain, like sun exposure, hanging upside down, cut down on caffeine, as well as some dietary supplements. A great way to increase cerebral blood flow has been shown to be through physical exercising at moderate intensity, according to this study. Stick to moderate exercise as there has been some evidence that very high intensity exercises can decrease cerebral blood flow.
So get that cerebral blood flowing through exercise, and see overall brain improvements!
2. Produces More (and Better) Neurons!
The brain loses neurons gradually as you age, and in response to certain events like excessive stress and drinking/drug use. It was once common wisdom that you can never grow new neurons once you are past a certain age, but studies show that to be false.
Neurogenesis, which is the scientific term for growing new neurons, does occur, especially in the hippocampus, which as we have seen, is responsible for processing memory and learning. So how do you get neurogenesis to occur?
It turns out that cardio exercise kicks in neurogenesis! In fact, in older individuals, usually the hippocampus shrinks, but by regular cardio exercise, it actually increases in size — along with an increase in memory and learning ability.
Another benefit to the hippocampus is that exercise increases BDNF (brain-derived neurotrophic factor) which helps strengthen the connections between neurons, and helps neurons survive.
Note that depression and high stress can hamper neuron growth. But as we will see, exercise helps alleviate that too. So exercise to get more healthy neurons for your brain and increase its power!
3. Releases Feel-Good Chemicals
Feeling good — and wanting to feel good — are the brain’s ultimate motivators. It’s the brain’s way of making sure we stay on the right track to survive — and thrive! To accomplish this reward system, the brain uses feel-good chemicals which are a set of neurotransmitters that are propagated through the brain to cause specific types of positive feelings.
Maximizing these mood enhancers does not just mean having more of them. It also means that the entire system in which they act, including the quality of the neurotransmitter receptors that receive them, are in top shape. Exercise is shown to maximize feel-good chemicals which contributes to good brain health. Let’s look at the main feel good chemicals and how exercise stimulates them.
Dopamine: This is the ultimate reward chemical. It’s a neurotransmitter that can be either exhibitory or inhibitory depending on the neuron receptor. Dopomine gives you a great feeling of accomplishment. It drives you to take action. It get’s released when you learn new things and accomplish goals. Since it feels so good to obtain that, it helps your focus, drive, competitiveness, and ambition.
You can maximize dopamine release by setting small goals and achieving them, as well as studying and exploring new areas and subjects. Note that some negative things can also release it, which can leave to addiction and undesirable behavior. Examples of that is excessive eating, drinking, drugs, smoking, gambling, sugar, excessive internet and social media use, and even greed in making money.
Exercise is a great, and positive way to cause your body to produce more dopamine and use it efficiently. It promotes the growth of dopamine receptors in neurons. Indirect benefits of exercise also helps, such as the accomplishment of physical and exercise goals. Also vitamin D promotes dopamine release and exercising outside in the sunlight will give you more vitamin D. Moderate exercise is all that is needed for dopamine release, so exercises such as brisk regular walking helps here.
Serotonin: While dopamine is more for goal-driven behavior, serotonin is important for being cool header, and emotionally stable, as well as have a general feeling of well being. Serotonin works with more of the reasoning part of the brain. So while dopamine will tend to make to want to go for immediate gratification, serotonin causes more impulse control and level headedness. It’s an inhibitory neurotransmitter.
Low serotonin can cause you to have a low mood, low energy and generally feeling negative. It’s also linked to having depression. In fact anti-depressants work on increasing serotonin.
Exercise can increase the serotonin in the brain and therefore helps prevent and fight depression, as well as generally makes you a happier person. Cardio exercise such as running, brisk walking and cycling increases serotonin.
Note that too intense exercise may actually hurt serotonin production in some cases. Also, like dopamine, being out in the sun will help produce serotonin.
Endorphins: Endorphins are the brain’s natural pain reliever. They help you cope with pain and intensive stress. It’s not meant to stop pain completely, otherwise the brain would just not have pain at all. It’s purpose is to balance the system and limit pain and intense stress once it starts – and as needed to continue survival. Endorphins also cause a very positive and relaxing feeling in the body.
Physical exercise, especially high intensity exercise, causes a lot of endorphins to be released. This makes you feel good, and helps boost self confidence, and reduces anxiety and stress. Also, it’s a great motivator to keep up exercising!
The relaxing effect of endorphins also help your stress level and improves your sleep. Some things besides exercise that releases endorphins are intense pain, eating hot peppers, laughing, and listening to music,.
Oxytocin: Oxytocin is sometimes referred to as the “Love” hormone. It encourages trust and intimacy, and is crucial to having relationships with others. It produces a feeling of reward that is activated when we are in a loving relationship, and experience physical touch and sex.
Humans are social beings, and being close to other people has always been important for survival. Oxytocin also makes us feel blissful, and reduces stress. Exercise — including low to moderate exercise like a leisurely walk — increases oxytocin.
Also if you exercise with others, it can give you another social outlook to further give you the benefits of this feel good chemical!
4. Improves your Sleep
Sleep is an essential part of brain health, as well as bodily health. The brain is actually very active during sleep — but it’s a different sort of activity than what occurs while you are awake.
During sleep, the brain processes and store memories. It will also distill and make tidy all the chaotic bits and pieces of thoughts, stimulus and experiences that happened during the day. It also reindexes memories and makes them easier to retrieve, as well as letting things learned sink in better.
Exercise is very helpful in sleeping well. One reason is that it helps tire you out, making you more ready for sleep. This is important in these modern days of sitting around a lot, working on computers and phones, and watching TV.
Fatigue is the best pillow.
Exercise also helps your sleep rhythm by raising your temperature slightly, which then causes it to lower making you more ready to sleep. It also helps you relax, have a positive mood, less stress, all very conductive to a great night sleep!
Note that it’s best to avoid exercise too close to bedtime though, although some can tolerate than more than others.
5. Lowers your Stress and Anxiety
Although it’s hard to see sometimes, the brain has very good intentions in providing stress and anxiety. It’s a way of prioritizing the brain and body’s resources for getting you out of danger — both real and percieved. It gives you an unpleasent feeling to incentivize you to escape the situation. It also releases cortisol as part of its fight or flight reflex, readying you for immediate action.
All this comes at the cost of being bad for your body, which the brain deems less important at the time. After all, are you worried about your blood pressure or it being bad for your heart when a lion is about to attack you? Once you have successfully run away from the lion or fought it somehow, the stress and anxiety goes away.
Our stress and anxiety system is somewhat too responsive for our current civilized environment though. We just do not have the dangers that we once did a long time ago. Sure, it still serves us from time to time, like when we are walking down a dark alley — but most of the time it kicks in for perceived dangers that just do not threaten our survival and basically does more harm than good.
High stress and anxiety can lower our immune system, make us gain weight, increase the risk for heart disease, makes us more frail, and affects our thinking and memory as well our mood. The brain cannot evolve on a dime to modern times though, so we just need to deal with it!
Exercise is a great way in this modern world to alleviate stress and anxiety. It gives an outlet for our fight or flight response without actually killing anyone or flat out running away! It also makes you stronger and more self confident which further reduces your cortisol level.
6. Increases your Cognition and Executive Function
Studies have found that the frontal and prefrontal cortexes are improved and larger in people who do regular physical exercises. This is where your logic thought and problem solving occur, as well as your executive functions that coordinates it all and drives actions toward a goal.
Exercise can help keep existing brain connections in these regions healthy and make new ones. Exercise also provides indirect help for your cognitive thinking and executive functions. This is because exercise itself can provide a stimulating enriched mental environment which is essential to prevent cognitive decline.
Also, since exercise helps you get more sleep, and has the other benefits on your mood and self confidence, all of this helps with the motivation to take on new mental challenges and execute on things that all help you think better and improve executive function. It gives you the motivation to think of new things and take actions.
Regular physical exercise helps your creativity as well as have been shown in studies. In addition to physical exercise, mind specific exercises can also be a great help for your cognitive and executive functions.
7. Helps Prevent Alzheimer’s
Exercise helps prevent neurological diseases such as Alzheimer’s disease and other forms of dementia. According to the Alzheimer’s Research & Prevention Foundation, regular exercise could reduce your risk of getting Alzheimers by up to 50%. Combine moderate intensity cardio and strength training for maximum results.
Also, a recent study of dementia in Swedish women, published in March 2018, showed that women of high fitness delayed the age of dementia occurring by 9.5 years compared to women of medium fitness.
There are many reasons that exercise can help prevent these diseases, although all are not known. One is through better brain circulation since it helps keep our neurons healthy. Also dementia and Alzheimer’s consist of impairment in the hippocampus and prefrontal cortex, which are helped by exercise as we have seen, by increasing volume of these regions and helping with neuron connectivity.
Regular physical exercise also has indirect abilities to help prevent Alzheimer’s. Getting more sleep, as well as lower stress and anxiety have been shown to reduce your risk — all of which exercise helps. Combine regular exercise with a healthy diet, like the Mediterranean Diet, for maximum protection.
So Get Out and Exercise!
Exercise has a lot of physical benefits and as we have seen, lots of mental ones as well. You don’t need to be a seasoned athlete or do very painful high intensity exercise to accomplish brain health. Regular brisk walking can go a long way toward providing these benefits. See my previous blog for the many benefits of regular walking: 8 ways that Regular Walking Enhances your Life
Combine regular walking with some occasional higher intensity cardio exercise as well as some strength training, and you will reap the benefits of a healthy body — and mind!
Be sure to check out our upcoming walking exercise app, Remote Walk!