TED日本語 - クリストファー・マクドーガル: 人類は走るために生まれたのか？

Running -- it's basically just right, left, right, left -- yeah? I mean, we've been doing it for two million years, so it's kind of arrogant to assume that I've got something to say that hasn't been said and performed better a long time ago. But the cool thing about running, as I've discovered, is that something bizarre happens in this activity all the time. Case in point: A couple months ago, if you saw the New York City Marathon, I guarantee you, you saw something that no one has ever seen before. An Ethiopian woman named Derartu Tulu turns up at the starting line. She's 37 years old, she hasn't won a marathon of any kind in eight years, and a few months previously she almost died in childbirth. Derartu Tulu was ready to hang it up and retire from the sport, but she decided she'd go for broke and try for one last big payday in the marquee event, the New York City Marathon. Except -- bad news for Derartu Tulu -- some other people had the same idea, including the Olympic gold medalist and Paula Radcliffe, who is a monster, the fastest woman marathoner in history by far. Only 10 minutes off the men's world record, Paula Radcliffe is essentially unbeatable. That's her competition.

The gun goes off, and she's not even an underdog. She's under the underdogs. But the under-underdog hangs tough, and 22 miles into a 26-mile race, there is Derartu Tulu up there with the lead pack. Now this is when something really bizarre happens. Paula Radcliffe, the one person who is sure to snatch the big paycheck out of Derartu Tulu's under-underdog hands, suddenly grabs her leg and starts to fall back. So we all know what to do in this situation, right? You give her a quick crack in the teeth with your elbow and blaze for the finish line. Derartu Tulu ruins the script. Instead of taking off, she falls back, and she grabs Paula Radcliffe, says, "Come on. Come with us. You can do it." So Paula Radcliffe, unfortunately, does it. She catches up with the lead pack and is pushing toward the finish line. But then she falls back again. And the second time Derartu Tulu grabs her and tries to pull her. And Paula Radcliffe at that point says, "I'm done. Go." So that's a fantastic story, and we all know how it ends. She loses the check, but she goes home with something bigger and more important. Except Derartu Tulu ruins the script again -- instead of losing, she blazes past the lead pack and wins, wins the New York City Marathon, goes home with a big fat check.

It's a heartwarming story, but if you drill a little bit deeper, you've got to sort of wonder about what exactly was going on there. When you have two outliers in one organism, it's not a coincidence. When you have someone who is more competitive and more compassionate than anybody else in the race, again, it's not a coincidence. You show me a creature with webbed feet and gills; somehow water's involved.

Someone with that kind of heart, there's some kind of connection there. And the answer to it, I think, can be found down in the Copper Canyons of Mexico, where there's a tribe, a reclusive tribe, called the Tarahumara Indians. Now the Tarahumara are remarkable for three things. Number one is, they have been living essentially unchanged for the past 400 years. When the conquistadors arrived in North America you had two choices: you either fight back and engage or you could take off. The Mayans and Aztecs engaged, which is why there are very few Mayans and Aztecs. The Tarahumara had a different strategy. They took off and hid in this labyrinthine, networking, spiderwebbing system of canyons called the Copper Canyons, and there they remained since the 1600s -- essentially the same way they've always been. The second thing remarkable about the Tarahumara is, deep into old age -- 70 to 80 years old -- these guys aren't running marathons; they're running mega-marathons. They're not doing 26 miles; they're doing 100,150 miles at a time, and apparently without injury, without problems.

The last thing that's remarkable about the Tarahumara is that all the things that we're going to be talking about today, all the things that we're trying to come up with using all of our technology and brain power to solve -- things like heart disease and cholesterol and cancer and crime and warfare and violence and clinical depression -- all this stuff, the Tarahumara don't know what you're talking about. They are free from all of these modern ailments. So what's the connection? Again, we're talking about outliers --

there's got to be some kind of cause and effect there. Well, there are teams of scientists at Harvard and the University of Utah that are bending their brains to try to figure out what the Tarahumara have known forever. They're trying to solve those same kinds of mysteries. And once again, a mystery wrapped inside of a mystery -- perhaps the key to Derartu Tulu and the Tarahumara is wrapped in three other mysteries, which go like this: three things -- if you have the answer, come up and take the microphone, because nobody else knows the answer. And if you know it, then you are smarter than anybody else on planet Earth. Mystery number one is this: Two million years ago the human brain exploded in size. Australopithecus had a tiny little pea brain. Suddenly humans show up -- Homo erectus -- big, old melon-head. To have a brain of that size, you need to have a source of condensed caloric energy. In other words, early humans are eating dead animals -- no argument, that's a fact. The only problem is, the first edged weapons only appeared about 200,000 years ago.

So, somehow, for nearly two million years, we are killing animals without any weapons. Now we're not using our strength because we are the biggest sissies in the jungle. Every other animal is stronger than we are -- they have fangs, they have claws, they have nimbleness, they have speed. We think Usain Bolt is fast. Usain Bolt can get his ass kicked by a squirrel. We're not fast. That would be an Olympic event: turn a squirrel loose -- whoever catches the squirrel, you get a gold medal. So no weapons, no speed, no strength, no fangs, no claws -- how were we killing these animals? Mystery number one.

Mystery number two: Women have been in the Olympics for quite some time now, but one thing that's remarkable about all women sprinters -- they all suck; they're terrible. There's not a fast woman on the planet and there never has been. The fastest woman to ever run a mile did it in 4: 15. I could throw a rock and hit a high school boy who can run faster than 4: 15. For some reason you guys are just really slow. (Laughter) But you get to the marathon we were just talking about -- you guys have only been allowed to run the marathon for 20 years. Because, prior to the 1980s, medical science said that if a woman tried to run 26 miles -- does anyone know what would happen if you tried to run 26 miles, why you were banned from the marathon before the 1980s? (Audience Member: Her uterus would be torn.) Her uterus would be torn. Yes. You would have torn reproductive organs. The uterus would fall out, literally fall out of the body. Now I've been to a lot of marathons, and I've yet to see any ... (Laughter) So it's only been 20 years that women have been allowed to run the marathon. In that very short learning curve, you guys have gone from broken organs up to the fact that you're only 10 minutes off the male world record.

Then you go beyond 26 miles, into the distance that medical science also told us would be fatal to humans -- remember Pheidippides died when he ran 26 miles -- you get to 50 and 100 miles, and suddenly it's a different game. You can take a runner like Ann Trason, or Nikki Kimball, or Jenn Shelton, you put them in a race of 50 or 100 miles against anybody in the world and it's a coin toss who's going to win. I'll give you an example. A couple years ago, Emily Baer signed up for a race called the Hardrock 100, which tells you all you need to know about the race. They give you 48 hours to finish this race. Well Emily Baer -- 500 runners -- she finishes in eighth place, in the top 10, even though she stopped at all the aid stations to breastfeed her baby during the race -- and yet, beat 492 other people. So why is it that women get stronger as distances get longer?

The third mystery is this: At the University of Utah, they started tracking finishing times for people running the marathon. And what they found is that, if you start running the marathon at age 19, you will get progressively faster, year by year, until you reach your peak at age 27. And then after that, you succumb to the rigors of time. And you'll get slower and slower, until eventually you're back to running the same speed you were at age 19. So about seven years,eight years to reach your peak, and then gradually you fall off your peak, until you go back to the starting point. You would think it might take eight years to go back to the same speed, maybe 10 years -- no, it's 45 years. 64-year-old men and women are running as fast as they were at age 19. Now I defy you to come up with any other physical activity -- and please don't say golf -- something that actually is hard -- where geriatrics are performing as well as they did as teenagers.

So you have these three mysteries. Is there one piece in the puzzle which might wrap all these things up? You've got to be really careful any time someone looks back in prehistory and tries to give you some sort of global answer, because, it being prehistory, you can say whatever the hell you want and get away with it. But I'll submit this to you: If you put one piece in the middle of this jigsaw puzzle, suddenly it all starts to form a coherent picture. If you wonder, why it is the Tarahumara don't fight and don't die of heart disease, why a poor Ethiopian woman named Derartu Tulu can be the most compassionate and yet the most competitive, and why we somehow were able to find food without weapons, perhaps it's because humans, as much as we like to think of ourselves as masters of the universe, actually evolved as nothing more than a pack of hunting dogs.

Maybe we evolved as a hunting pack animal. Because the one advantage we have in the wilderness -- again, it's not our fangs and our claws and our speed -- the only thing we do really, really well is sweat. We're really good at being sweaty and smelly. Better than any other mammal on Earth, we can sweat really well. But the advantage of that little bit of social discomfort is the fact that, when it comes to running under hot heat for long distances, we're superb, we're the best on the planet. You take a horse on a hot day, and after about five or six miles, that horse has a choice. It's either going to breathe or it's going to cool off, but it ain't doing both -- we can. So what if we evolved as hunting pack animals? What if the only natural advantage we had in the world was the fact that we could get together as a group, go out there on that African Savannah, pick out an antelope and go out as a pack and run that thing to death? That's all we could do. We could run really far on a hot day.

Well if that's true, a couple other things had to be true as well. The key to being part of a hunting pack is the word "pack." If you go out by yourself, and you try to chase an antelope, I guarantee you there's going to be two cadavers out there in the Savannah. You need a pack to pull together. You need to have those 64-, 65-year-olds who have been doing this for a long time to understand which antelope you're actually trying to catch. The herd explodes and it gathers back again. Those expert trackers have got to be part of the pack. They can't be 10 miles behind. You need to have the women and the adolescents there because the two times in your life you most benefit from animal protein is when you are a nursing mother and a developing adolescent. It makes no sense to have the antelope over there dead and the people who want to eat it 50 miles away. They need to be part of the pack. You need to have those 27-year-old studs at the peak of their powers ready to drop the kill, and you need to have those teenagers there who are learning the whole thing all involved. The pack stays together.

Another thing that has to be true about this pack: this pack can not be really materialistic. You can't be hauling all your crap around, trying to chase the antelope. You can't be a pissed-off pack. You can't be bearing grudges, like, "I'm not chasing that guy's antelope. He pissed me off. Let him go chase his own antelope." The pack has got to be able to swallow its ego, be cooperative and pull together. What you end up with, in other words, is a culture remarkably similar to the Tarahumara -- a tribe that has remained unchanged since the Stone Age. It's a really compelling argument that maybe the Tarahumara are doing exactly what all of us had done for two million years,

that it's us in modern times who have sort of gone off the path. You know, we look at running as this kind of alien, foreign thing, this punishment you've got to do because you ate pizza the night before. But maybe it's something different. Maybe we're the ones who have taken this natural advantage we had and we spoiled it. How do we spoil it? Well how do we spoil anything? We try to cash in on it. We try to can it and package it and make it "better" and sell it to people. And what happened was we started creating these fancy cushioned things, which can make running "better," called running shoes.

The reason I get personally pissed-off about running shoes is because I bought a million of them and I kept getting hurt. And I think that, if anybody in here runs -- and I just had a conversation with Carol; we talked for two minutes backstage, and she's talking about plantar fasciitis. You talk to a runner, I guarantee, within 30 seconds, the conversation turns to injury. So if humans evolved as runners, if that's our one natural advantage, why are we so bad at it? Why do we keep getting hurt?

Curious thing about running and running injuries is that the running injury is new to our time. If you read folklore and mythology, any kind of myths, any kind of tall tales, running is always associated with freedom and vitality and youthfulness and eternal vigor. It's only in our lifetime that running has become associated with fear and pain. Geronimo used to say that, "My only friends are my legs. I only trust my legs." That's because an Apache triathlon used to be you'd run 50 miles across the desert, engage in hand-to-hand combat, steal a bunch of horses and slap leather for home. Geronimo was never saying, "Ah, you know something, my achilles -- I'm tapering. I got to take this week off," or "I need to cross-train. I didn't do yoga. I'm not ready." Humans ran and ran all the time. We are here today. We have our digital technology. All of our science comes from the fact that our ancestors were able to do something extraordinary every day, which was just rely on their naked feet and legs to run long distances.

So how do we get back to that again? Well, I would submit to you the first thing is get rid of all packaging, all the sales, all the marketing. Get rid of all the stinking running shoes. Stop focusing on urban marathons, which, if you do four hours, you suck. If you do 3: 59: 59, you're awesome, because you qualified for another race. We need to get back to that sense of playfulness and joyfulness and, I would say, nakedness, that has made the Tarahumara one of the healthiest and serene cultures in our time. So what's the benefit? So what? So you burn off the Haagen-Dazs from the night before?

But maybe there's another benefit there as well. Without getting a little too extreme about this, imagine a world where everybody could go out their door and engage in the kind of exercise that's going to make them more relaxed, more serene, more healthy, burn off stress -- where you don't come back into your office a raging maniac anymore, where you don't go back home with a lot of stress on top of you again. Maybe there's something between what we are today and what the Tarahumara have always been. I don't say let's go back to the Copper Canyons and live on corn and maize, which is the Tarahumara's preferred diet, but maybe there's somewhere in between. And if we find that thing, maybe there is a big fat Nobel Prize out there. Because if somebody could find a way to restore that natural ability that we all enjoyed for most of our existence, up until the 1970s or so, the benefits, social and physical and political and mental, could be astounding.

So what I've been seeing today is there is a growing subculture of barefoot runners, people who got rid of their shoes. And what they have found uniformly is you get rid of the shoes, you get rid of the stress, you get rid of the injuries and the ailments. And what you find is something the Tarahumara have known for a very long time, that this can be a whole lot of fun. I've experienced it personally myself. I was injured all my life, and then in my early 40s I got rid of my shoes and my running ailments have gone away too.

So hopefully it's something we can all benefit from. And I appreciate you guys listening to this story. Thanks very much.

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