Posted on April 18, 2012

Why Kenyans Make Such Great Runners: A Story of Genes and Cultures

Max Fisher, The Atlantic, April 17, 2012

Two hours, 31 minutes, and 51 seconds after the Boston marathon began on Monday, its male and female champions had already finished. A few minutes later, race-watchers noticed something. The first, second, and third-place men were all Kenyan. So were the first, second, and third-place women. It was yet another amazing showing for Kenyan runners, and yet another reason to ask: how?

For such a popular, straightforward question, there’s less consensus than you might think. Western research on the nature of Kenyan runners, and on successful African athletes in general, is complicated by some particularly thorny racial politics. There’s a nasty history, after all, to white scientists evaluating the physical attributes of Africans. But that hesitancy to really study Kenyan runners’ success has allowed some probably false, and often culturally reductive, theories to persist. The scientific research hits on some of the most sensitive racial anxieties of Western-African relations, but it’s also an amazing story of human biodiversity.

The statistics are hard to ignore. This medium-size country of 41 million dominates the world in competitive running. Pick any long-distance race. You’ll often find that up to about 70 or 80 percent of its winners since the late 1980s, when East African nutrition and technology started catching up with the West, have been from Kenya. Since 1988, for example, 20 of the 25 first-place men in the Boston Marathon have been Kenyan. Kenyan women appear to have had a later start, winning none of marathons before 2000 (possibly due to discriminatory laws and a tradition of forcing girls into marriages, both of which were partially rolled back by 1990s reforms) and 9 of 13 since then. {snip}

It turns out that Kenyans’ success may be innate. Two separate, European-led studies in a small region in western Kenya, which produces most of the race-winners, found that young men there could, with only a few months training, reliably outperform some of the West’s best professional runners. In other words, they appeared to have a physical advantage that is common to their community, making it probably genetic. The studies found significant differences in body mass index and bone structure between the Western pros and the Kenyan amateurs who had bested them. The studied Kenyans had less mass for their height, longer legs, shorter torsos, and more slender limbs. One of the researchers described the Kenyan physical differences as “bird-like,” noting that these traits would make them more efficient runners, especially over long distances.

Surprisingly, Western popular writing about Kenyans’ running success seems to focus less on these genetic distinctions and more on cultural differences. For years, the cultural argument has been that Kenyans become great runners because they often run several miles to and from school every day. But, about a decade ago, someone started asking actual Kenyans if this was true, and it turned out to be a merely a product of Western imaginations: 14 of 20 surveyed Kenyan race-winners said they’d walked or ridden the bus to school, like normal children do. Another cultural argument says they run barefoot, which develops good habits, but if this were true then surely the far more populated countries of South Asia, where living without shoes is also common, would dominate over Kenyans. Another ascribes it to the “simple food” of Kenya, but this again is true of many parts of the world, and Kenya’s not-so-great health record suggests the country has not discovered the secret to great nutrition. And there is a cringe-inducing theory, still prevalent, that Kenyans’ history as herders means they get practice running as they chase their sheep across the countryside.

{snip}

It’s hard to talk about the subject without revealing some bias, or giving the impression of trying to explain away their success, or hitting on some still-fresh cultural wound from centuries of exploitation. This may be why definitive answers seem so hard to find, and why we tend to embrace theories that downplay legitimate biological distinctions and emphasize the idea that Kenyans simply work harder. But this kind of thinking, though clearly well intentioned, is a kind of condescension in itself. We’re so afraid of reducing Africans to their physical attributes that we’ve ended up reducing them to an outdated stereotype: Cool Runnings, the barefoot village boy who overcame.

{snip} Most of Kenya’s Olympic medal winners come from a single tribe, the Kalenjin, of whom there are only 4.4 million. Sub-Saharan Africans have identified themselves by tribes such as this one for far longer than they’ve identified by nationality — a system mostly imposed by the Western colonialism — so the Kalenjin distinction is not just academic, and the tribe is probably genetically insular enough that common physical traits could inform their athletic success.

In 1990, the Copenhagen Muscle Research Center compared post-pubescent schoolboys there to Sweden’s famed national track team (before Kenya and a few other African countries began dominating international racing events in the late 1980s, Scandinavians were the most reliable winners). The study found that boys on the high school track team in Iten, Kenya, consistently outperformed the professional Swedish runners. The researchers estimated that the average Kalenjin could outrun 90% of the global population, and that at least 500 amateur high school students in Iten alone could defeat Sweden’s greatest professional runner at the 2,000-meter.

A 2000 Danish Sports Science Institute investigation reproduced the earlier study, giving a large group of Kalenjin boys three months of training and then comparing them to Thomas Nolan, a Danish track superstar. When the Kalenjin boys trounced him, the researchers — who had also conducted a number of physical tests and compared them against established human averages — concluded that Kalenjins must have an inborn, physical, genetic advantage. They observed a higher number of red blood cells (which lent new credence to the theory that elevation makes their bodies more effective oxygen-users) but, in their conclusions, emphasized the “bird-like legs” that make running less energy-intensive and give their stride exceptional efficiency.

{snip}