Sporting achievement is down to our natural inheritance. It's in the genes. That appears such a statement of the obvious that one wonders how or why anyone could object. Introduce race into the equation, however, and you have an explosive mix.

Sporting achievement is down to our natural inheritance. It's in the genes. That appears such a statement of the obvious that one wonders how or why anyone could object. Introduce race into the equation, however, and you have an explosive mix.

I can't say I'm really surprised by this anxiety. As a young boy growing up in North London, I found that my mixed heritage confused a great many people, white and black. To a degree, it still does. Polarised views of ethnicity, based on skin colour, focused my mind as a child on the meaning of both black and white.

At school, many of my teachers and fellow pupils expected me to be good on the sports field. I vividly recollect the reaction to my modest teenage athletic triumphs. The overwhelming majority insisted that I was good because I was black. Fewer were interested in my English mother's not inconsiderable athletic credentials. Although it may well have been in the blood - a euphemism for genetic inheritance - it was assumed it was in "the black bits".

Recently, the American journalist Jon Entine has caused an enormous furore in the United States with his book Taboo: Why black athletes dominate sports and why we're afraid to talk about it, precisely because he's come up on the nature rather than the nurture side of the argument. Entine argues that it is not a coincidence that all the world's leading sprinters have a West African heritage.

Certainly, there are few other human activities where natural ability and performance is so readily measurable as in running. The pattern of achievement at the highest levels makes a prima facie case for black superiority. Of the top 200 times at 100 metres, not one has been run by a white athlete. Only black sprinters have dipped under the magic 10 second barrier. In the middle distances, the Kenyans appear to have cornered the market in gold medals.

Science has tried to pin down the magic ingredients that seem to make men of West African heritage faster. There's a lot of theorising around higher percentages of fast-twitch muscle fibres in the legs, and higher levels of testosterone leading to greater amounts of explosive energy for black athletes. Many of these body type differences appear to have a genetic basis - that is, they are inherited. But here we must tread with caution, because whether these genetically determined characteristics translate into sporting success remains largely in the realms of conjecture.

In the late 1970s, Henrik Larsen was coaching middle-distance Danish national champions. He was intrigued by the competitive drubbing the Kenyans dished out to his star athletes. Wanting to know more, he travelled to Kenya. He went to the region where the Kalenjin tribe has lived for generations, high up on the Great Rift Valley that slices through the eastern part of the African continent. Larsen's trip spawned a research project which, he says, is now concluding that the Kalenjin have a genetic advantage when competing in endurance running - in every race, from the 800 metres up to the marathon.

The hypothesis is based on a long-term study carried out at the Copenhagen Institute of Sports Science in Denmark. The researchers believe that the Kalenjin runners have an ability to take on board oxygen in just the same way as fit Europeans, but their bodies are more efficient at using that on-board fuel. The Kalenjin can also run at higher speeds for longer than Europeans at the same fitness level. The theory is that the genes of the Kalenjin have probably mutated to adapt to living in hot, dry conditions at high altitude.

The Copenhagen team is absolutely clear, however, that race is not a variable in its research. It would be a mistake to apply the results to the entire population of Kenya, let alone the entire world's black population. As such, skin colour is incidental.

While race and racism may be alive and well in the imaginations of many people in multiracial societies, science is slowly piecing together a jigsaw which reveals that there are more genetic differences within racial groups than between them. It has long been understood by biologists and geneticists that the scientific concept of race is virtually useless as a means of classifying the human family.

Sport, especially at the time of the Olympics, is good place to discuss these matters. Athletic achievement has always been a double-edged sword for black people. Winning has ironically reinforced the stereotype that black people are somehow less evolved than white people and therefore retain more "natural endowments", fuelling the perverse logic that brains and physical ability are mutually exclusive.

There are, of course, other legitimate explanations than genetic predisposition, for why there are so many black sporting champions. Professor Ellis Cashmore at Staffordshire University says that racism itself has a part to play. Sport is an arena where black people are allowed to achieve. It creates role models, and there's nothing like success to breed success.

In a perverse way, the mythology surrounding the notion that black sporting achievement is down to natural ability may give black athletes a psychological edge. They believe the myth, too, and they'll work harder to achieve athletic success.

That's not to say that genes are irrelevant. When I talked to Colin Jackson, our own 110-metre hurdle gold medal prospect, he told me that he was lucky to have inherited his parents' genes. Both parents were gifted athletes. That isn't an issue of skin colour or race; it's an issue of biology. Of course, whatever the natural inheritance, there still has to be a lot of training and luck to ensure that it finds its way to the champion's podium.

So what about an answer to the question, do black men run faster? The evidence suggests that we've simply been asking the wrong question. We're so used to thinking in terms of black and white and employing the terminology in everyday language, that we unthinkingly attach these categories to the sports results. Scientifically, it turns out to be meaningless.

What champions such as Linford Christie, Michael Jordan, Daley Thompson and Marion Jones have is genetically unique. If it weren't, there would be a lot more of them around. In fact, they show us how important individuality is. We should get away from race-defined success and celebrate the individuality of a champion.

Britain is a much more mixed place than it was when my generation was growing up. All of us, white, black and - increasingly - brown, now have the chance to release ourselves from this bondage of racialised history. The prize is one that all our children deserve to share. A timely recognition that, although in our differences we are many peoples, the message from science is loud and clear: we are but one Human Race.

Kurt Barling reports on 'The Faster Race' (BBC2), Thursday, 9.40pm