Have you ever wondered why people run marathons? It all started way back in 490 BC with a Greek messenger named Pheidippides. He ran from the town of Marathon to Athens, a distance of 26.2 miles, to announce that the Greeks had defeated the Persians. Unfortunately, after delivering the message, he collapsed and died. Despite this, marathons have become a popular sporting event today. But why do people run them for fun, and how can our bodies handle such a long distance? Let’s dive into the fascinating world of marathons and human evolution!
Believe it or not, our journey to becoming runners began millions of years ago. Our ancestors started walking on two legs over three million years ago, and soon after, they began running. While many animals can run faster than us in short sprints, humans are built for long-distance running. Even the fastest animals, like cheetahs, can only run short distances before they overheat. In contrast, humans can run for miles and miles, making us unique in the animal kingdom.
Our ability to run long distances may have helped our ancestors hunt and gather food more effectively. This, in turn, allowed us to evolve larger brains. Our bodies have several features that make us great runners. For example, we have large tubes in our skulls to help us balance, reflexes in our eyes to keep our heads steady, and short arms and thin ankles that require less effort to move. Our wide shoulders, thin waists, and narrow pelvises help counterbalance our moving legs. We also have sweat glands and less body hair to help us stay cool while running.
Running a marathon is not just about having strong muscles; it’s also about energy. Our bodies use a molecule called ATP for energy, similar to how a car uses gasoline. Our muscles contain proteins called actin and myosin, which work together to contract and move. This process is powered by ATP, which our bodies constantly replenish using mitochondria, the powerhouses of our cells.
During a marathon, our bodies burn through a lot of ATP. To keep going, we need to eat and drink to replenish our energy stores. Our muscles prefer glucose, which is stored as glycogen for quick access. However, even glycogen isn’t enough for a marathon, so runners need to consume additional energy during the race to avoid “hitting the wall.” This term describes the fatigue that occurs when the body runs out of energy, causing dizziness and disorientation.
Running a marathon is not just a physical challenge; it’s a mental one too. Runners often find themselves battling their own minds, pushing through feelings of fatigue and pain. It’s a test of willpower and determination. Completing a marathon is an incredible achievement, and it teaches us a lot about our bodies and what we’re capable of.
So, whether you’re a runner or just curious about the science behind marathons, it’s clear that humans are uniquely equipped for long-distance running. Our evolutionary history, combined with our mental strength, makes us capable of achieving amazing feats. Who knows, maybe one day you’ll be inspired to run a marathon yourself!
Research the story of Pheidippides and the historical context of the Battle of Marathon. Create a short presentation to share with the class, highlighting the significance of his run and its impact on modern marathons.
Explore the evolutionary traits that make humans good long-distance runners. Create a poster or infographic that illustrates these traits and explains how they contribute to our endurance capabilities.
Participate in a simulation where you track your energy levels during a hypothetical marathon. Plan a diet that includes the necessary nutrients and energy sources to sustain you throughout the race, and explain your choices.
Design a basic training plan for someone preparing to run a marathon. Include physical exercises, mental strategies, and nutritional advice. Present your plan to the class, explaining how each component helps prepare for the race.
Engage in activities that build mental resilience, such as mindfulness exercises or visualization techniques. Discuss how these strategies can help overcome the mental challenges of running a marathon and apply them to other areas of life.
Sure! Here’s a sanitized version of the transcript:
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[MUSIC] In 490 BC, a Greek messenger named Pheidippides ran from the Greek town of Marathon to the capital, Athens, to deliver the message that the Greek army had just defeated the Persians. The distance between those two towns is 26.2 miles, which is the origin of the modern sporting event we call the marathon. You might know that story, but what is often not mentioned is that when he arrived in Athens after running those 26.2 miles, Pheidippides died. So why would anyone want to run a marathon for fun? How are our bodies even able to do it? I decided to find out, so I ran one.
In the process, I discovered a lot about what I’m made of, in more ways than one. Are you ready to run the marathon? My training started millions of years before I ever got to the starting line. The first step to becoming a runner is, well, standing up. Bipedalism is only seen in a handful of animals. For most species, walking on two legs is just a temporary form of transportation. Our ancestors first stood up over three million years ago, and we were probably running not long after that. You could say that humans are built for long-distance running, but the truth is, long-distance running has shaped us. Four-legged animals could easily beat me in a sprint, but humans are contenders in nature’s distance running events. Even the cheetah, the most perfectly crafted running machine on Earth, can only run for about a mile and a half before overheating. Today’s fastest Olympic marathoners would only be beaten by a handful of Earth’s animals in long-distance events.
One theory of human evolution suggests that our adaptations for distance running contributed to hunting success, which we discussed in my episode “Why Do We Cook?” Bigger, richer meals allowed us to evolve larger brains. There’s a whole list of ways that we are made to run. Large tubes in our skulls help us balance while running, reflexes in our eyes keep our heads steady as we move, and our short arms and thin ankles require less effort to swing. Wide shoulders, a thin waist, and a narrow pelvis help counter the rotation of our moving legs. We have sweat glands, less body hair, and tall, thin bodies that help us disperse heat. Our bodies also have better blood flow away from the brain to keep it cool, large gluteus maximus muscles to stabilize our upper body, and high surface area knee, ankle, and hip joints for shock absorption. Most importantly, our lower legs are built like rubber bands.
This is by far our most remarkable running adaptation. Every time my body hits the ground, it delivers up to eight times the force of my body weight. That’s over 1400 pounds! To sustain that for 26.2 miles, my foot expands and spreads like a shock absorber. The most important part of a running human is the Achilles tendon. When my foot hits the ground, my calf muscles flex, and even then, the muscles and tendons are still a bit elastic. My ankle joint acts as a lever, transferring as much as 50 percent of that energy into the next step. By using stored kinetic energy instead of chemical energy, we can go farther with less effort.
You can’t run a marathon on just rubber bands, though. You need energy, which humans derive from ATP, similar to how a car runs on gasoline. This is an image of striated muscle, the same type we have in our arms, legs, and basically everywhere we move. Each row of stripes contains a string of proteins called actin, next to another string called myosin. The head of the myosin protein acts like a ratchet, pulling along the actin string, shortening and contracting the muscle. That myosin machine is powered by ATP. However, our bodies only have a couple of seconds’ worth of ATP stored at any moment, so we constantly replenish it, thanks to our mitochondria and their ATP factories. Picture me as a giant ship with trillions of mitochondria at the oars. My body cycled through something like 75 kilograms of ATP during the marathon—that’s almost my entire body weight! It shows how efficient our bodies are at recycling energy.
Now, that 75 kilograms of ATP broken down releases the same amount of free energy as a kilogram of TNT. My body generates ATP in a couple of different ways. If I were running full speed the entire time, my cells would have to use an inefficient process called glycolysis. However, by running slightly slower for the whole race, I allowed my mitochondria to use a much more efficient method called the Krebs cycle and the electron transport chain. I can burn various fuels to make ATP, such as fat or protein, but my muscles prefer glucose, which is stored in long chains like glycogen for quick access. However, even glycogen stores aren’t enough for a marathon, so I had to eat and drink more during the race to avoid hitting the dreaded wall.
Hitting the wall is just a term for fatigue, and there are many reasons it can happen. If you run out of glycogen, your muscles can run out of ATP, causing the protein ratchet to get stuck. If your cells don’t have enough salt, your nerves and muscles won’t have the sodium, potassium, and calcium they need to pass electrical signals. The main reason people hit the wall is that your brain competes with your muscles for blood sugar. If those levels dip too low, you’ll feel dizzy and disoriented.
“I think I’m gonna die. I’m gonna die.”
“You’ll be okay.”
Your brain actually prevents your muscles from firing to conserve energy. I’ve never run a marathon before, and I discovered it’s not like any other sporting event I’ve participated in. You’re not battling an opponent; you’re only battling yourself. All those feelings of joy, fatigue, and pain exist only in your mind. That mind is connected to the physical muscles and chemical processes doing the work. I’ve never understood more about my body and biology, and when I pushed them to the limit, I discovered that it wasn’t a limit after all. That was the most fun I’d never want to experience again. Halfway through, it was the hardest thing I’ve ever done, and the entire second half was pure willpower—a competition against myself—and I won. I overcame my own mind. That was incredible. Thank you, everyone.
We’re not the only social animals that sit down to eat together, but we are the only ones who cook. Cultural anthropologist Claude Lévi-Strauss suggested that cooking establishes the difference between animals and people, although I think he’d agree that clothing makes a significant difference too.
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Let me know if you need any further modifications!
Running – The act of moving rapidly on foot, often used as a form of exercise or sport. – Running regularly can improve cardiovascular health and endurance.
Evolution – The process by which different kinds of living organisms develop and diversify from earlier forms during the history of the earth. – The evolution of species is driven by natural selection and genetic variation.
Muscles – Tissues in the body that have the ability to contract and produce movement or maintain the position of parts of the body. – Strong muscles are essential for athletes to perform at their best.
Energy – The capacity to do work, which in biological terms is often derived from nutrients and used by cells to perform various functions. – The body converts food into energy to fuel physical activities like sports.
Glucose – A simple sugar that is an important energy source in living organisms and is a component of many carbohydrates. – During exercise, muscles use glucose as a quick source of energy.
Marathon – A long-distance running race, traditionally covering a distance of 42.195 kilometers (26.219 miles). – Completing a marathon requires extensive training and stamina.
Fatigue – A state of physical or mental weariness resulting from exertion or prolonged activity. – After a long workout, athletes often experience muscle fatigue.
Ancestors – Organisms from which others have descended, often referring to earlier forms in evolutionary history. – Our ancestors adapted to different environments, leading to the diversity of species we see today.
Distance – The amount of space between two points, often used to describe the length of a race or the separation between locations. – In track events, runners compete over various distances, from sprints to long-distance races.
Mitochondria – Organelles found in large numbers in most cells, where biochemical processes of respiration and energy production occur. – Mitochondria are often referred to as the powerhouses of the cell because they generate most of the cell’s supply of ATP, used as a source of chemical energy.
