I'm so excited to tell you all about today's book! It's called 'Real Happy Pill'. Let's get our happy hormones flowing! It's as simple as moving our bodies. As you can probably guess from the title, this book is all about brain science. It's no surprise that brain science is a hot topic in our get-together! It's so appealing to a group of scientifically literate people who care about personal growth.

Our brain is an amazing thing! It's so incredible! It's only the size of two fists and weighs about as much as a carton of milk, but it contains a hundred billion neurons – that's about the same number of stars in the entire galaxy! It's not an exaggeration to say that each of us has our very own little universe in our brains! Your brain is like a little universe! It stores everything you've experienced since birth, all the habits you've developed, all the aspects of your personality, all your memories, and all the knowledge you've learned, including every book you've ever read and every episode of an audiobook such as the one you're listening to right now. The brain is probably the most structurally complex thing we know, yet it uses less energy than a light bulb! Given all these amazing facts, the author of today's book starts off by saying, "If a man isn't interested in the brain, then I'm afraid there's nothing else that can fascinate him."

The author of this wonderful book is Anders Hansen, a Swedish mental health expert and an extremely influential science writer in the field of brain science. His wonderful books on brain science have sold more than 3 million copies worldwide! One in ten people in Sweden has read one of his books. The most influential of these is the one we're reading today, Real Happy Pill. Let's give our brains a boost by getting our bodies moving! The great news is that exercise helps our brains to work better! Let me be really clear: when you work out, your brain gets smarter!

I know this might sound a little strange at first, but stick with me! Most of us go to the gym to get in shape, or to strengthen our cardio, improve our flexibility, and live a healthier life. And that's great! If anyone said, "I go to the gym to exercise my brain," you might think they were a little crazy! As we all know, fitness is based on the principle of "you grow what you train". If you want to have stronger arms, then go and practice dumbbell curls! If you want to have stronger shoulders, then go and practice pull-ups! So, by the same token, if you want a smarter brain, you should go and do those thinking exercises, right? Why not have some fun and play a crossword puzzle, do some memory exercises or even try your hand at Sudoku? The lovely folks over at today's book have shared some interesting news. It seems that these so-called thinking exercises don't have as big of an impact on the brain's ability to improve as we thought. It's really quite fascinating! Even walking, running and regular strength training, which we might think of as purely physical exercises, can effectively develop our brain functions. I think it's safe to say that the brain is one of the organs of your entire body that benefits the most from physical activity!

I'd love to know more about the specific areas of benefit! In his lovely book, author Anders Hansen focuses on five abilities of the brain: resistance to stress, concentration, resistance to depression, memory, and creativity. It's so great to see how brain science research over the last decade or so has shown that physical activity has a really positive effect on all five of these abilities! This is such an exciting conclusion! Of course, we just need to figure out the science behind it! I'm really excited to share with you in the next section how sports can help to improve each of these five areas of brain function. The great thing is that there are so many different ways to get the boost you need! The exact type of exercise you do to improve these five abilities will depend on the principles behind it. In the last part of the show, I'll give you a quick overview of the specific advice given in the book to help you take the right approach to exercise to boost your brain performance. I really hope you've heard the end of it, my friend.

Alrighty, now let's dive into the next section, which I'm really excited to share with you! Let's get our happy hormones flowing and give our brains a boost by moving our bodies!

Let's start with something really important: how exercise helps your brain to resist stress.

Let's dive in and figure out what happens in our brain when we feel stressed. This is where a regulatory mechanism called the HPA axis comes in. If you know a thing or two about brain science, you might find these next two minutes useful as a quick refresher. I'll do my best to keep it simple and clear for you.

So, let's start with the basics. What is the HPA axis? The 'H' stands for hypothalamus, the 'P' for pituitary gland and the 'A' for adrenal gland. Our bodies are so clever! These three parts are arranged in a top-down order. The hypothalamus is part of the brain, and it's located at the very bottom of the brain, right at the base. Right below that is the pituitary gland, which is an endocrine gland. And our lovely adrenal glands are located above our kidneys. So, when something scary happens, like a hungry lion coming your way, your brain is on high alert. It sends a signal to the pituitary gland, which then releases a hormone that travels through your body to your adrenal glands. And then, when the pituitary gland gets the signal, it immediately lets out a hormone that zips through your bloodstream to your adrenal glands. The adrenal glands then secrete cortisol, which is like a little boost to your heart, making it beat faster and stronger. This is to get your body ready for fight or flight, so it's good to know your body is on the case! It's incredible how quickly this whole process happens! It only takes a second or so from the time you see the lion to your heart racing.

In a nutshell, the cortisol that the adrenal glands secrete is what makes you feel stressed. This example of a lion encounter we've just described would have only happened in prehistoric times, when our ancestors were hunting on the African savannah. Even in the modern world, though, we still feel stress from cortisol, and more often than in prehistoric times. This is because there are more things in modern life that our brains recognise as "threats", and while the vast majority of these things don't actually threaten our lives, they do cause real stress. For example, we all know how it feels when we're under pressure from a loan, or when we're criticised by our leaders, or when our families urge us to do something. Another thing that sets these modern stressors apart from the lions on the savannah is that they stick around for a while. When you encounter a lion, you either fight or run. And when you win the fight or run away, the crisis is lifted and your cortisol levels will soon drop, returning your mind and body to a state of relaxation. But many of the modern world's stressors can stick around for quite a long time. I'm talking about a loan, for example. That can take ten or twenty years to come to fruition, and in that time, it'll probably still be on your mind. It might not be as scary as a lion, but it seems to be more difficult to deal with than a lion.

Let me put it another way. You'll see that in most situations in modern life, cortisol isn't really necessary. When you're facing a lion, fight or flight, your body goes into a pretty tense state, doesn't it? But when you think about loans, about an exam next month, a public presentation you have to do tomorrow, and your heart pounds, it doesn't really help solve the problem. In fact, it might even mess up your mind and affect your performance! So, here's the big question: how do you get your HPA axis to chill out and stop secreting so much cortisol over everything?

Actually, it's not your HPA axis that's causing all the fuss. Let's take a little peek at the next layer up, shall we? Our lovely brains have a part called the amygdala that directly controls the HPA axis. The amygdala is like a sentinel that is always on alert, ready to protect us. When it senses that we're in danger, it sends a signal to the hypothalamus to kickstart the HPA axis. That's not much up to this point, but the amygdala has a special quality that makes it more active when stimulated by cortisol. So, when the HPA axis is activated, the cortisol produced by the HPA axis will in turn stimulate the amygdala, making it even more nervous about urging the HPA axis to produce more cortisol. This is how the amygdala and the HPA axis form a kind of dance that keeps repeating itself. If this were the only set of mechanisms in our brain, they would keep spinning faster and faster in response to each other's stimulation until they turned into a flywheel. Our lovely brains would then be flooded with cortisol and plunged into deeper and deeper fear.

It's so sad, but this condition is actually the cause of many fear-based types of mental illness. It's so important for our brains to be able to switch off the alarm function of the amygdala when we need to. Guess which part of the brain is in charge of this? It's our hippocampus! The hippocampus and the amygdala are like the brake and the gas pedal. Whenever the amygdala's alarm bells go off and it's clamouring for cortisol production, the hippocampus comes out to soothe it and help calm it down. Thankfully, the hippocampus is always there to calm things down. Once the crisis is over, the amygdala stops alarming the hippocampus and cortisol returns to normal levels. As we chatted about earlier, there are so many sources of stress in our modern lives, and they can stick around for a long time. Our modern lives are pretty stressful, and our bodies are having to deal with a lot more than our ancestors did when they were roaming the African savannah. This means our amygdala is on high alert a lot more often than it was back then. It's like the gas is always on, and the brakes can be a bit of a challenge! Our poor hippocampus gets worn out over the years as it tries to keep up with the amygdala. And as we all know, another really important job of the hippocampus is to store our precious memories. This is why lots of people who are feeling anxious for a long time often say that their memory is getting worse. They might forget things or even meet new people and not be able to remember their names! This is actually because their hippocampus, which acts as a brake pad for the amygdala, has become worn.

I know it can be really frustrating when things don't work as they should. So, I'm going to tell you if it's possible to repair worn-out brake pads. And that's the wonderful news that today's book is going to share with us! The great news is that experiments have shown that exercise can help to repair and strengthen the hippocampus, which is really encouraging!

Our lovely brains shrink a little as we get older, bless them! This process usually starts around the age of 25. As we get older, our brains shrink a little bit each year. On average, they shrink by about 0.5% to 1% from the previous year. Our lovely hippocampus, which is part of our wonderful brain, also naturally shrinks at an average rate of 1% from the previous year. It's totally normal for our memories to play tricks on us as we get older. But it's not our fault! It's all down to the shrinking hippocampus.

Now that we've got that all figured out, let's dive into this next experiment together. In 2011, a lovely team of researchers from the University of Pittsburgh got together 120 subjects between the ages of 55 and 80 and randomly divided them equally into two groups. One group was to take part in regular endurance training, which involved going for 40-minute walks three times a week. The other group was to do exercise at the same frequency, but at a gentler pace and without any big changes in heart rate during exercise. At the beginning and end of the year, the lovely researchers measured the size of the hippocampus of each of these subjects. The lovely researchers also found that the 60 subjects whose heart rates didn't change much during exercise had an average reduction in hippocampus size of 1.4%. Given their age, this is perfectly normal. The really amazing thing was that instead of shrinking, the hippocampus actually grew by 2% in those who did endurance training consistently for a year! In other words, after a year of physical activity, the hippocampus of these people was not a year older, but two years younger – pretty amazing, right? And there's more! Among these 60 people, the stronger the body, the more the hippocampus grew.

This experiment was so well done that it even made the annual report of the American Association for the Advancement of Science that year! Since then, lots of other scientific research organisations around the world have done similar experiments, and the results are really consistent! It seems that regular aerobic exercise can slow down or even reverse the hippocampus shrinkage. This is really interesting! We've just been chatting about how the hippocampus and amygdala are like the brake and gas pedal. The great news is that regular aerobic exercise helps the hippocampus to grow. This allows it to apply the brakes to the amygdala more effectively, which is really beneficial. The fitter the hippocampus, the more calm the amygdala will be when faced with a crisis. It helps you to stay calm in stressful situations because it doesn't overreact and produce excess cortisol. This is how exercise helps you to cope better with stressful situations. We often say that those top athletes have a "big heart". Even in the world-class tournament to play the key points, they will not panic, causing errors. It's not quite right to say they have a "big heart" from a brain science point of view. It's more accurate to say that their large hippocampus gives them the ability to stay calm in dangerous situations.

Memory

Now that we've chatted about the hippocampus, let's have a little catch-up on memory.

The hippocampus is the memory centre of the brain. The great news is that exercise helps our hippocampus to grow, which is fantastic for our memory! But that's just one of the many wonderful ways that exercise helps our memory!

And there's more! Exercise helps us remember new things in at least two other ways. The great thing about exercise is that it helps to increase the amount of blood flowing through our brains, which is really good for our memory! This is great news for our brains! It means that brain cells can get all the energy and sustenance they need to thrive, and they can process information more effectively. I just wanted to draw your attention to something really important. To get your brain into this active state, you need to make sure you don't overdo it. Keep the intensity of the exercise within a reasonable range and you'll be absolutely fine. If you choose strength training with heavy weights, the type used in fitness to increase muscle dimension, then when you lift iron, your blood will flow more to the muscles in the area of force, and the blood flow through the brain will be reduced in turn. I'm sorry to say that this won't help you to remember things better.

And there's more! Exercise also has a wonderful effect on our brains. It helps to stimulate the cerebral cortex and hippocampus, which in turn produces an amazing protein. This amazing protein is called Brain Derived Neurotrophic Factor, or BDNF for short. Don't worry, we'll keep it simple! All you need to know is that BDNF is a wonderful thing for our brains! It does so many good things for us. It also protects our brain cells, especially the little ones that are just starting out, from harmful substances and helps them to survive hypoxia or hypoglycaemia. It also helps our brains to adapt and to stay young for longer. The lovely folks over at The Brain Gym say we can think of BDNF as a "natural fertiliser for the brain" that is versatile and plays an important role in many of the brain's activities.

And guess what? BDNF also plays a key role in memory! So, let's start by taking a closer look at how our amazing brains work and how they build those wonderful memories we all love! Let's take a break from all the brain science jargon for a moment and try to explain things in a way that's easier to understand. If we imagine the brain as a vast universe, each brain cell is like a star, and memory fragments are like constellations of these stars. When we need to remember something, our amazing brains activate a constellation of brain cells, which is like a three-dimensional network of cells. This network stores information, and our brains can then extract that information when we need it.

It's really interesting to learn that the network of cells used to store our memories isn't always as strong as it could be. It's so important to keep on learning and training so that our brains can keep on strengthening the connections between the cells in our memory networks. And guess what? BDNF is like a powerful adhesive in this process! It's like a helpful glue that makes it easier for our brain cells to connect and help us to remember things more easily.

Now that we understand this principle, let's look at a practical application together. In his book, the lovely Anders Hansen asks a fascinating question: could running help you play the piano well? I know this question might sound a little strange at first, but now that you know a bit more about how BDNF works, you'll see that before learning any new skills or knowledge, a little bit of exercise can really help you learn more effectively. I know it might sound a bit silly, but I think it's helpful to think of exercise as mixing the cement before building a wall. Once you've done the exercise, you'll feel ready to start learning, and you won't feel overwhelmed when you start to build your knowledge brick by brick.

Concentration

Now that we've chatted about how exercise can help our memories, let's dive into how it can help us focus.

The good news is that the brain science principles for this are a little simpler than those mentioned earlier. In a nutshell, exercise produces dopamine, which is great for boosting concentration!

Dopamine is probably the best-known of the body's hormones, and for good reason! I'd highly recommend listening to the book 'Greedy Dopamine'. It's a fascinating read that delves deeply into the physiological mechanisms of dopamine in the human body. But it doesn't stop there! It also explores the impact of dopamine on the individual and on society as a whole. If you're interested, I'd love for you to give it a listen! The title of the book, Greedy Dopamine, is so fitting! Dopamine is basically a "craving molecule." It makes us crave tasty treats and the opposite sex, and the things we crave are mostly good for our survival and reproduction.

So, you might be wondering, why does exercise produce dopamine? It might seem a bit strange, but exercise actually uses up our physical energy and makes us more likely to get injured. This doesn't seem like a great idea for survival! So, it's a bit of a puzzle why our bodies reward us for doing it. The lovely folks over at The Brain Gym suggest that it might be because exercise was our ancestors' way of exploring the world. Our ancestors didn't have the same conveniences we have today, like being able to order takeaway when you're hungry and food coming to your door. Our ancestors had to travel long distances in search of food in the vast grasslands. When they found it, they had to do everything in their power to subdue it so that they could have something to eat. This way of surviving was all about making sure our brains knew that sports like running and fighting were good for us. Even though we don't exercise to hunt like our ancestors did, we still burn off fat to stay alive. Our brains haven't caught up yet! They still work with our kidneys to secrete dopamine when we exercise, encouraging us to run even faster.

And you might be wondering what the connection is between dopamine and focus. As you can see from the example of exercise, the dopamine-secreting cells are like a cheerleading squad in our body. When they cheer us on, we just can't get enough of the task at hand! And that's when our focus is at its strongest! But this cheerleader has its own preferences, and it will only cheer for what interests it. If it decides that what we are doing has little to do with survival and reproduction, it loses interest and becomes a little demoralised. So, at this point, without hearing those cheerleaders, our brain loses energy for the task at hand. It's like it's looking for something else to do in order to regain the attention of those cheerleaders! That's when our attention naturally wanders and we start to lose focus.

So, it's only natural to wonder whether activities like reading and studying are often too challenging for cheerleaders. How can we keep our eyes on the prize? This is where exercise comes to our rescue with a programme that helps us build up a bit of a head of steam in advance. Dopamine-secreting cells just love to see us moving about, so let's give them a little "show" before we learn. It's great to get your body moving at this time! You can make sure you're working out at an appropriate intensity to give your brain and kidneys a boost and help them produce more dopamine. By the time we sit down and start learning, our bodies still have plenty of dopamine to give! Our wonderful brains still hear all that loud applause and cheering, which keeps them energised and ready to take on the task at hand! The great thing is, as long as you exercise enough, your body can keep producing lots of dopamine for hours on end. This means you'll find it really easy to focus on your studies during that time!

The wonderful thing about exercise is that it can help us fight depression.

Depression is something that many of us experience from time to time. It doesn't always come with strong negative emotions like sadness or anger. Depression is often just a cold, boring feeling of loss of interest in life, which is totally normal. Have you ever wondered what can help us feel more interested in life? From what we know about how our brains work, we've already mentioned two kinds: dopamine and BDNF.

Dopamine is the "desire molecule", and it's no surprise that it can stimulate our desire for certain things. But have you ever wondered why BDNF plays a similar role?

This brings us to something really interesting in the world of brain science. It's called "pattern separation." I know this term sounds quite impressive, but I promise you it's very simple! The term 'pattern separation' is all about recognising those subtle differences! The author of today's book gives us a great example. Imagine you go to a cocktail party and there's someone you feel really familiar with. You're almost certain you've seen him once or twice before, but for the life of you, you can't remember who he is!

Oh my, who on earth is he? As you think about this, your brain is busy comparing this person's face to all the other similar faces in your memory. The lovely dentate gyrus, which is a tooth-shaped protrusion in the hippocampus, plays a really important role here. The dentate gyrus is really good at pattern separation, which basically means spotting the little differences between things that look similar. I bet you played a game as a child where you had to find a few differences between two almost identical images! When you played this game, the most active part of your brain was probably the dentate gyrus.

The reason we're chatting about the dentate gyrus and its superpower of pattern separation is because folks who are feeling blue don't have that ability. For someone who is feeling depressed, the world can seem a bit dull and grey, as if everything has lost its sparkle. This is exactly why their dentate gyrus isn't working as it should. It makes it hard for them to notice the little differences between things. So, how can we help these lovely people to revitalise their dentate gyrus? As we chatted about earlier, the good old BDNF that exercise produces can really help to regenerate brain cells. The great thing about BDNF is that it acts on the hippocampus, which then responds quickly to the stimulation by generating new brain cells. The good news is that the pattern separation ability of depressed people will also become sharp again! They'll be able to see the world in all its wonderful richness and variety again, which will really help them to come out of their depression.

And let's not forget creativity!

And now for something really exciting! Let's talk about how exercise can help to boost creativity in the brain.

I'm sure you've probably heard lots of examples of this already. The wonderful Japanese author Haruki Murakami wrote a beautiful book called What I Talk About When I Talk About Running. In this lovely book, Haruki Murakami shares his routine while writing a book. He would wake up bright and early at 4 a.m. and work away until 10 a.m. After a tasty lunch, he would go for a 10-kilometre run, followed by a refreshing swim. Once he'd finished his workout, he'd relax with some reading and music before heading to bed at 9 p.m. sharp. He truly believed that regular exercise helped him to stay fit and healthy, and it also gave him lots of inspiration to create.

Haruki Murakami's experience is definitely not an isolated case! It's so inspiring to see how many successful people in creative fields believe that they come up with more great ideas when they are exercising! Guess what! Even Einstein, Beethoven, Darwin and Kant – all of these leading thinkers in different fields – had the habit of taking long walks. And they all generated highly creative ideas during their walks! And right here in our own backyard, we have the amazing Steve Jobs, who started the wonderful tradition of walking meetings at Apple. This practice was also picked up by the brilliant Mark Zuckerberg, who founded Facebook, and Jack Dorsey, who founded Twitter. They both felt that meetings were more productive when held while walking!

Could exercising in a way that we all enjoy, like going for a walk, really help us to be more creative? The lovely folks over at Stanford University have done a study that shows this is true! The lovely folks over at Stanford University conducted a group experiment with 176 subjects, and the results were pretty amazing! It turns out that after a little walk, people's ability to come up with creative ideas and brainstorming increased by a whopping 60%! I'd love to know more about this! Brain scientists have come up with a fascinating conjecture that we'd love to see tested further! They think that exercise might just change the way the thalamus works!

The thalamus is a really important part of our brain, right at the centre. Its job is to act as a filter for information, which it does really well! Our senses send loads of information to our thalamus, which then filters it all and lets us focus on the bits that matter. This layer of filtering is super important! It helps to make sure our cerebral cortex doesn't get overwhelmed with too much information and goes into downtime. But when we exercise, it seems that the thalamus opens up a bit when it comes to filtering information. This is great because it means that more information than usual can enter our consciousness, which can lead to lots of creative ideas! I'll be keeping an eye out for new developments in this area and I'll be sure to let you know when there's something new to report!

And that's a wrap! I've shared the heart of this book with you, and I hope it's been as inspiring as I've found it to be. I'm not going to end this listening session by repeating the principles of brain science that I've covered earlier, so let's do a more practical summary together! I came across some really helpful tips in the book that I think you'll find useful for getting the most out of your exercise routine.

1. To really feel the benefits of exercise on your brain, try to work out for at least 30 minutes. 45 minutes is even better!

2. The best way to get the most out of your exercise routine is to do it three times a week.

3. It's really important to keep your heart rate up when you exercise. Just to give you a little extra boost, it's great to keep your heart rate at 70-75% of its own limit for improved concentration. I'd like to share two reference values with you. For people in their 40s, it's great to keep your heart rate during exercise at 130-140 beats per minute. For people in their 50s, it's even better to keep it at 125 beats per minute!

4. It's so important to do aerobic exercise! We also know that strength training is great for the brain, but we're still waiting to find out exactly how it works! The great news is that all five of the brain functions we've mentioned today can be enhanced by aerobic exercise!

5. Just a heads-up: try to avoid exercising too intensely. If you feel really tired after exercising, don't worry! It's not the end of the world. Your memory and creativity won't improve significantly if you're feeling this way.

And finally, just remember to take it easy on yourself! And finally, it's so important to make sure you exercise regularly and consistently over time. It's so worth putting in the time and effort to make these fundamental changes in your brain! It'll take months, if not longer, to create new brain cells and blood vessels and enhance the connections between different brain regions. It's totally doable! Just keep exercising three times a week for six months or more and you'll be amazed at how much better your brain will feel.