Race, Genes and Running

Dennis Kimetto, fastest slow-twitch man in the world

One of the most notable phenomena in competitive running over the last one or two generations has been the dominance of African runners or runners of African descent.

While it is still politically incorrect to say it in many quarters, it is now incontrovertible that the explanation is largely genetic. Disagreement on this, at least by informed sources, is ideological, not scientific.

But this tells only half the story. Among black runners, those of West African descent (henceforth, "West Africans") dominate sprinting or short-distance races while East Africans or those of East African descent (henceforth, "East Africans") dominate long-distance events. Indeed, the "split" between the two groups is almost total. No East Africans have made it into the ranks of elite sprinters, while no West Africans have made it into the ranks of elite long-distance runners. While both groups obviously have black skin, they are quite different genetically. 

West Africans have generally competed for Nigeria, Great Britain, Jamaica and other Caribbean countries, Canada and the United States. East Africans have generally competed for Kenya and Ethiopia. There are a few other countries involved and exceptions such as ex-pats, etc.

Here are some interesting facts and figures:

• In the last eight Olympic games, 71 of the 72 runners in the 100 meter finals have been West Africans (I believe one was from Fiji). Their dominance has been almost complete.
• Out of the top all-time 125 times for the marathon (26.2 miles), East Africans have 121 spots and North Africans (all from Morocco) 3. The sole "white" athlete to clock a top 125 performance - Ryan Hall, recording a 2:04:58 time at the 2011 Boston Marathon - participated in a bizarre weather race where the runners had a huge tailwind for the entire course (Hall was fourth behind three East Africans). The world record for the men's marathon was set by Kenyan Dennis Kimetto, running a 2:02:57 at Berlin in 2014.
• Recently, white athletes have perhaps started to make small inroads in the long-distance category - Galen Rupp's Silver medal in the 2012 Olympic 10,000 meters being the most conspicuous examples.
• West African dominance is nowhere near as great in the 110 meter hurdles. I have yet to see a satisfactory explanation for this.
• In women's races, Africans have dominated but not as completely. In this year's Olympic women's marathon, white and Asian runners took five of the top ten spots, though they won no medals. The non-East African group featured three Americans, one Belorussian and one North Korean. 14 of the top 25 women's marathon times have been run by East Africans. Although, notably, the world record and indeed the fastest three times were run by a white athlete - Paula Radcliffe of Great Britain.    

I'm not going to go into a long and boring explanation as to why genetics is determinative here. But the numbers above are very suggestive, and counter-theories quickly break down. For example, those arguing for a "cultural" explanation need to account for how, say, a champion sprinting culture seems to track athletes of West African descent (and only athletes of West African descent) in wildly different countries and societies - the Caribbean, North America, Europe and West Africa itself.

Let me now make three crucial points:

First, genetic distributions are just that, distributions. To say that East Africans may be genetically "superior" in long-distance running is to make a claim about statistical averages and merely means you are likely to find a higher than normal set of runners that have, say, the potential to run a Marathon in under 2:10:00 among East Africans than for other groups. It's perfectly possible that a white runner might end up being an international marathon champion. But of course, since the set is smaller, the odds are lower.

Second, genetics determines potential, not ultimate performance. Potential must always be met with proper training. The fact that white runners used to dominate (more than one or two generations ago) can almost certainly be ascribed to East African countries previously failing to have the resources to adequately train or field teams that could compete internationally (and hand in hand with that, fewer athletes from Kenya or Ethiopia even realized that they might have international potential). This changed in the last two decades of the 20th century.

Third, ascribing running potential to genetics does not take away from the deserved honor or praise for the individual athletes. All Olympic athletes were gifted with "good" genes for their particular sports. But they complemented their biological luck with smart and hard-work. Michael Phelps has a perfect swimmers body - an anatomically unusual body in many ways - but he had to train for years to take proper advantage of it.

What do we mean by good genes for runners?

Obviously, there is no one "sprinter's gene" or "marathoner's gene." Rather, genetic endowments give one a certain "package." These days, international running is so competitive that one must have top scores in every element of the package to race at an elite level.

What goes into such a package?

Some of it is visually obvious. Sprinters often look like lean football players. They have large chests, large biceps and large thighs - all for pumping over short distances. Long distance runners have smaller thighs (though thickly-muscled ones) and their upper bodies are often almost emaciated. For long-distance runners, what you have above the waist - whether fat or muscle - is often worse than meaningless. It's just excess weight.

For women, who almost always have much less bulky muscles, the difference is less pronounced. It's always been interesting to me how some female long-distance runners (though not all) almost look a bit chunky. And I should say that as a male long-distance runner who has often been over my ideal running weight, this fact annoys me.

What you can't see, however, is also important. Look at a picture of a muscle. Everyone has a combination of white and red (or fast-twitch and slow-twitch) muscle fibers in their muscles, a combination that is mostly genetic. Whites give you temporary explosive power; reds give you sustained power. If you have more fast-twitch fibers, then you're a sprinter and quite honestly have virtually no potential to excel at long-distance running. If you have more slow-twitch fibers, then you're a long-distance runner and will never be able to sprint very well. This is pretty much an iron law and it partly explains why, say, some of your friends like "jogging" or running 5Ks and some don't.

Of course, certain sports demand a basic competence in both. Bruce Jenner did well enough on average in both categories to win the Olympic decathlon. But whatever his muscle composition (fast-twitch vs slow-twitch - I suspect he was a fast-twitch man), he would never have had the potential to be an Olympic champion in both sprinting and long-distance running.

What length differentiates sprinting from long-distance? The answer is a distance somewhere between 400 and 800 meters. Champion 100 meter runners have often been champion 400 meter runners. 800 meter athletes have been competitive in long-distance races from the mile to the marathon. But as far as I know, no 400 meter runners have ever excelled at 800 meters, and vice versa.

It would be fascinating to see a 600 meter race with the football players competing against the emaciated skeletons. Though, oddly, these races are rare. Appropriately, the last 200 meters of the 800 is often referred to as the "shadow" or "death zone" part of the race. You can go all out for a bit more than 400 meters, but that won't get you to the finish line. You have to have the proper "gas" to complete the last lap.

Other important factors for long-distance running include your V02 max - the efficiency at which your body converts oxygen to blood back into your muscles. V02 max is important but not all-important. Studies have shown that elite East Africans have good V02 max ratings - as any long-distance runners would - but ratings not significantly higher than, say, top whites or Asians. Lance Armstrong has an extremely high V02 max, as one might expect, but he only managed to clock a 2:59:36 in his first marathon - good for an amateur - but far short of elite level. One of the top endurance athletes of all time only managed to beat my best marathon time by 6 minutes! (To be fair, Armstrong ran a 2:46:43 the next year.)

Which brings us to body type and form. (Armstrong's cyclist's body differs significantly from a runner's body and will be inferior for running, even compared with that of amateurs such as myself.) In body type and form, East Africans also seem to have a large advantage for running. One East African observer wrote:

A group of us were sitting watching a local competition one day . . . A British runner was over here in Kenya running against us. We noticed first the big difference in leg structure; his legs were like oak tree trunks whereas ours were like willows. When we jumped we floated over; when he jumped it was a major upheaval (quoted in The Lore of Running by Tim Noakes, p. 442).

Again, this only really comes to the fore in elite competition where all parts of the "package" must be close to optimum.

As the reader can tell, I find the whole subject fascinating, though I hope it doesn't seem obsessively so.

One final caveat is this. Your genetic endowment obviously cannot be changed. But you do have control over how you make use of it. Among other things, you may discover modes of training that will render your particular distribution more useful to you, perhaps overcoming whatever small disadvantages you might have against others. This is why it's not surprising to me that the era of almost complete East African dominance might be coming to an end (or at least a partial end), as non-East Africans get even more scientific about their training. Though, of course, the East Africans are also getting more scientific...

And here's a last thought about race. Or should I say "racism"? In the United States, it's often looked upon as "racist" to dwell on genetic differences between races. But  at least as far as athletic performance goes, to me, non-genetic theories can often seem just as "racist," if not more so than any other.

For example, it is still occasionally alleged that Kenyans are faster because they had to run to school as kids. As if everyone in Africa lived in huts miles away from the nearest one-room schoolhouse run by missionaries or whatever. It took years for any earnestly non-racist Western theorist to actually ask any Kenyan athletes whether this was really true. One just laughed:

The school was right next to my home. I never would have run there. What do you think I am, crazy?