The Sports Gene: Inside the Science of Extraordinary Athletic Performance (21 page)

Manners was banking on the western Rift Valley’s fountain of talent when, in 2005, he held KenSAP’s first “great tryout,” as he calls it. While scientists and running enthusiasts have assayed Kenyan dominance every which way to make points about whether or not Kenyan runners are genetically gifted for endurance running, Manners’s tryout—which has the goal of helping poor Kenyan kids get into elite colleges—is more truly a random sample of Kalenjin than nearly any scientist has ever taken and put on the track. The kids in his time trials generally come from elite, highly selective, government-funded boarding schools, and essentially none of them have any racing experience. This is panning for endurance gold in its most raw form.
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Each year, about half of the boys in the time trial will run faster than 5 minutes and 20 seconds in the 1,500-meter time trial, on a shoddy dirt track, above seven thousand feet. (The 1,500 is about 100 meters shy of a mile, and 5:20 translates to a mile time just over 5:40.)
“Can you imagine, if you considered a comparable group from any American upper-echelon academic selection?” Manners asks. “I mean, it would be nowhere near that.”

In the tryout in 2005, a boy named Peter Kosgei ran 4:15 with no real training. Kosgei was accepted to Hamilton College in Clinton, New York, and quickly became the best athlete in the college’s history. In his freshman year, Kosgei won the Division III 3,000-meter steeplechase national title.
By the end of his junior year, he had compiled eight more national titles in cross-country and track. His skill was so out of place in Division III that his teammate Scott Bickard compared it to “going to a Division III school to play basketball and you find yourself playing with a guy who can play in the NBA.”

Sadly, Kosgei was unable to compete in track during his senior year. On a trip home to Kenya during spring break in March 2011, Kosgei was mugged and left with two broken legs. When I met him at a KenSAP function eight months later, Kosgei was pursuing a graduate degree in chemistry and told me that he aspired to race again one day. At Hamilton, he said, he trained a paltry thirty to thirty-five miles a week, and thus felt that he had only grazed the outermost layer of his potential.

A slew of other KenSAP runners have met quick success. Evans Kosgei—no relation to Peter—held down a 3.8 GPA in computer science and engineering at Lehigh University and, after adjusting to life in America for a year, decided to go out for cross-country in his sophomore year. He struggled even to finish his five-mile tryout. But, in short order, Kosgei was running at the Division I national championships in both cross-country and track. In 2012, he was named Lehigh’s Graduating Scholar-Athlete of the Year.

Manners says that many KenSAP students have no interest in running, and some of those who were welcomed by American coaches quickly dropped the sport to focus on academics. But of the seventy-one KenSAP students through 2011—none with significant prior training experience—fourteen made varsity NCAA rosters.

Of course, stumbling upon hidden distance running talent is not
exclusive to Kenya. And, as with Jamaican sprinting, it is the very systematizing of the process by which talent is stumbled upon that makes it less like stumbling
and more like tactical filtering. The ultimate question is whether finding endurance talent is more likely to occur in Kenya, or specifically among the Kalenjin, and whether that is largely due to innate biological characteristics. For certain sports, it’s obvious and uncontroversial that particular populations will have a greater or lesser frequency of gifted prospective athletes. Pygmy populations have an average adult male height of around five feet. So, while they may produce an NBA player someday, a basketball scout taking a random sample from a Pygmy population will discover fewer athletes who, given the proper training, might make the NBA than if the sample were taken in Lithuania.

Presently, there is no way to know how the KenSAP time trial would compare with a similar exercise focused on a different ethnic group in Kenya or somewhere else in the world, and the KenSAP tryout isn’t intended to be a scientific experiment. There was one research group, though, that tried to get at the answer in a scientific manner.

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Beginning in 1998, a team of researchers from the University of Copenhagen’s world-renowned Copenhagen Muscle Research Centre set out to put data behind the many anecdotes and arguments about Kalenjin distance running dominance. Among the theories they sought to investigate: that members of the Kalenjin tribe might have a particularly high proportion of slow-twitch muscle fibers in their legs; that Kalenjin people are born with higher aerobic capacity (VO
₂
max); and that Kalenjin people might respond more quickly to endurance training than members of other ethnic groups.

To untangle at least a segment of the nature from the nurture, the scientists set out to study not only elite runners, but also Kalenjin boys who lived in cities and those who lived in rural villages, as well as Danish boys living in Copenhagen.

Overall, the findings did not support any of the long-standing but uninvestigated theories. Elite runners from the Kalenjin tribe and from Europe did not differ on average in their proportion of slow-twitch muscle fibers, nor did Danish boys differ from Kalenjin boys who lived in cities or those who lived in rural villages. Kalenjin boys from villages did have higher VO
₂
max than Kalenjin boys from cities, who were much less active, but it was similar to the VO
₂
max of the active Danish boys. And Kalenjin boys, as a group, did not on average respond to three months of endurance training—as measured by aerobic capacity—to a greater degree than did Danish boys.

As expected from their latitudes of ancestry, though, the Kalenjin and Danish boys did display body type differences. A greater portion of the body length of the Kalenjin boys was composed of legs. The Kalenjin boys were, on average, two inches shorter than the Danish boys, but had legs that were about three quarters of an inch longer.

The scientists’ most unique finding, though, was not the length of the legs, but their girth. The volume and average thickness of the lower legs of the Kalenjin boys was 15 to 17 percent less than in the Danish boys. The finding is substantial because the leg is akin to a pendulum, and the greater the weight at the end of the pendulum, the more energy is required to swing it.
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Biologists have demonstrated this in humans in controlled conditions. In one particularly well-controlled study, researchers experimented with adding weights onto different parts of runners’ bodies: the waist, the upper thigh, the upper shin, and around the ankle.

Even when the weight stayed the same, the farther down the leg it was placed the greater the energetic cost to the runners. In one phase, each runner had to wear eight pounds around his waist, which required about 4 percent more energy to run at a given pace compared
with when he wasn’t wearing eight pounds of weights. But when the runners were subsequently equipped with a four-pound weight on each ankle they burned energy 24 percent more rapidly while running at the same pace, even though their total weight had not changed one ounce from the previous condition.

Weight that is far out on the limbs is called “distal weight,” and the less of it a distance runner has, the better (i.e., if you have thick calves and ankles, you won’t be winning the New York City Marathon). A separate research team calculated that adding just one tenth of one pound to the ankle increases oxygen consumption during running by about 1 percent. (Engineers at Adidas replicated that finding in the process of constructing lighter shoes.) Compared with the Danish runners, the Kalenjin runners tested by the Danish scientists had nearly a pound less weight in their lower legs. The scientists calculated the energy savings at 8 percent per kilometer.

“Running economy” is the measure of how much oxygen a runner utilizes to run at a given pace. Much like the fuel economy of a car, you get a certain amount of bang for a certain amount of gas, and that differs according to the size and shape of the car. Elite distance runners have both high VO
₂
max and good running economy. Or, to continue the car analogy, the rare mix of a big engine and good fuel economy. Among elite runners, all of whom have large engines, running economy often differentiates the extremely great from the merely very good.

And on that measure, untrained Kalenjin boys were better than untrained Danish boys. Proportionally long legs and thin lower legs contribute separately to good running economy, and they had both.
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Even the Kalenjin city boys, who were less active and less aerobically fit than the Danish boys, started with better running economy. Both
within and between groups of Kenyan and Danish runners, lower leg thickness was an important predictor of running economy. Among Danes and Kenyans who were training similar mileage each week—or not training at all—Kenyans had superior running economy.

That is, when they were using the same proportion of their oxygen-carrying capacity, the Kenyans were going faster for that same effort. As one might expect from the artificial selection for body types that occurs in high-level sports, elite Kenyan runners had even more narrow lower legs—and much better running economy—than did untrained Kenyan boys. One of the scientists, Bengt Saltin, among the most prominent exercise scientists in the world, wrote: “the relationship seems to confirm that the lower leg thickness expressed in absolute terms is a crucial factor for running economy.” Later, Henrik Larsen, another researcher in the Copenhagen group, declared: “We have solved the main problem” of Kenyan running dominance.

Lithe legs help running economy no matter one’s nationality or ethnicity. One of the best running economies ever measured in a laboratory belonged to Eritrean runner Zersenay Tadese, the world record holder in the half marathon as of this writing. The measurements, taken in a lab in Spain, show that Tadese does not have particularly long legs—his legs are only slightly proportionally longer than those of elite Spanish runners—but they are considerably narrower. Interestingly, Tadese grew up dreaming of a career in competitive cycling—one of the first national sports federations formed in Eritrea was for cycling—but found vastly more success when he switched to running just prior to his twentieth birthday, placing thirtieth at the World Cross Country Championships in his very first season in 2002, before winning the world title in 2007. Surely, Tadese’s aerobic fitness from cycling carried over to running, but his thin lower legs are an advantage best exploited on the track, not the bike.

As Tadese proves, it isn’t as though thin lower legs are confined to the Kalenjin. But the Kalenjin do, in general, have a particularly linear build, with narrow hips and long, thin limbs. Some anthropologists
actually refer to the extreme of a slender body build as the Nilotic type—“Nilotic” refers to a set of related ethnic groups residing in the Nile Valley—and, it so happens, the Kalenjin are a Nilotic people.
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The Nilotic body type evolved in low latitude environments that are both hot and dry, because the long, thin proportions are better for cooling. (Conversely, the extreme of the short, stocky build was historically known as the Eskimo type, though the term “Eskimo” has been replaced in some countries, where it is considered derogatory.) And the Kalenjin are as low latitude as it gets. When I visited Kenya in 2012, while driving between training sites I crisscrossed the equator. But the Kalenjin initially migrated to Kenya from southern Sudan, where other Nilotes live today, like the Dinka, an ethnic group known for its tall and slender constituents. A few very long-limbed professional basketball players have been Dinka—most notably Manute Bol, who was 7'7" and reportedly had a wingspan that was 8'6".

Given that the linear build is helpful for endurance running, and that Nilotic people tend to have a linear build, it occurred to me that there should be a wealth of running talent in southern Sudan. But long-distance runners from Sudan are almost absent from international competition. I asked both scientists and track-and-field experts if they had any insight into whether Sudanese runners have been tested for running economy, or why we don’t see Nilotic distance runners coming out of Sudan. Unfortunately, there is no data at all on Sudanese runners, and the consensus among track experts was that, unlike Kenya, which apart from postelection violence has been relatively stable, modern Sudan has been in a constant state of tumult and violence that has curtailed opportunities for athletes.

In December 2011, I attended the Arab Games in Qatar and spoke with Sudanese athletes and journalists who told me that, among other
problems, like travel difficulties, athletes from the southern regions of Sudan (now the nation of South Sudan) had historically been discriminated against and that national sports officers did not enter skilled athletes from that area in past Olympics. Plus, civil war has raged for the better part of a half century in the exact area where the Nilotic people reside, leaving no sports culture or infrastructure whatsoever in southern Sudan. So I approached the question the only way I could think of: looking for south Sudanese running talent outside of southern Sudan.

The first I ever wondered about Sudanese athletes was when I wrote a story about Macharia Yuot, a runner at Widener University in Pennsylvania who caught my eye by winning the 2006 Division III cross-country championship in Wilmington, Ohio, before jumping on a plane that evening and finishing sixth in the Philadelphia Marathon—his first run longer than twenty-one miles—the very next morning. Yuot had been one of the “Lost Boys of Sudan,” the largest contingent being from the Nilotic Dinka, who fled the violence that engulfed their homes. When he was nine, Yuot’s town was overrun by the religious civil war that cost two million Sudanese their lives between 1983 and 2005. Rather than see their sons forced to walk minefields in order to clear the way for soldiers, parents bid them flee. So the boys walked the desert, alone. By 1991, some, like Yuot, who survived the soldiers hunting them—and the lions that occasionally carried away a sleeping boy—made it to a refugee camp in Kenya. In 2000, the U.S. government airlifted around 3,600 of the boys to America, and sprinkled them around the country with foster parents.