Kenya's Rift Valley, where everyone runs
Kenya produces some of the world's very best distance runners, but the possibility of winning Olympic gold is not the only incentive for the country's athletes.
On the drive up into the lush hills of Iten, 2,600m (8,530ft) above sea level, we pass groups of children on their way to school.
The odd one is dawdling in a way that would seem familiar anywhere in the world, but most are running - and running fast - with a carrier bag of books swinging from one hand.
One 13-year old boy called Kenneth tells me how he runs back and forth to school every day and even runs back home for lunch.
Each run takes 40 minutes, but he has long, lean legs and says he likes it.
Like a lot of children living in the hills of western Kenya when he grows up, he wants to be an athlete. Why? Because, he tells me, then he could afford to help his family and his whole village.
With heroes like David Rudisha who holds the 800m world record, the children see that athletics can be an escape from poverty, but runners here are so good that the competition is stiff.
From Our Own Correspondent
- Broadcast on Saturdays at 11:30 BST on BBC Radio 4, and weekdays on BBC World Service
The times that would guarantee you a place on the national team of many European countries would leave you as one of many runners-up in Kenya.
But this exceptional pool of talent brings athletes another opportunity.
An hour from the green peace of Iten I pull over by a line of single-storey whitewashed building with rusty corrugated iron roofs.
The fence which keeps the cows away is draped with shiny tracksuits - purple, red and black - drying in the sun. This is a training camp for the young people with one aim in mind - to use their running talent, not to go for gold, but to get them a scholarship to an American university.
It is early but they have already been for a 45-minute run into the hills and soon they are putting their damp tracksuits back on before jogging across the road, and ducking through a gap in the fence to get to the track - a bumpy, grassy field, marked out with chalk.
Then they begin their training session sprinting diagonally across the track, then jogging slowly round the edge, then sprinting across once more - again and again.
After 30 minutes they begin their stretches and tell me of their plans.
Nowami wants to be a nurse, Beatrice, a molecular scientist and Susteen a TV news anchor, but they know that what the Americans want them for is their speed.
Provided they train hard enough as well as passing their exams and satisfying the strict criteria for visas, they can go to the US.
The best runners here have very slim, long lower legs, so slim they almost look fragile.
Scientists have found that this does bring an advantage, as does living and training at such a high altitude, but the athletes are not keen on the suggestion that it is down to genetics.
They do not like the implication that this means they do not have to try. And they certainly do try.
In fact one athlete told me that the motivation to run your way out of poverty is so strong, that if Kenya were to become a rich country he believed it would stop producing such fast runners.
I go to another village where three primary schools are holding a competition. They are determined to include all children in the sports day, not just the best, but coaches and even an Olympic Gold medallist - Asbel Kiprop - have come to see who shows promise.
The children are told to line up by age.
They are very excited. Every single one wants to run.
The seven-year-olds go first, flinging off their shoes and then sprinting 70m across the bumpy field.
I do a bit of running myself, or maybe I should call it jogging, so I had come in my running shoes, thinking I might join in.
I was planning to wait to run with the older children, but that was until I saw how fast the seven-year-olds went.
So I asked the eight-year-olds if I could be in their race. Their enthusiasm results in several false starts, with me already lagging behind because I was a bit slow on the off.
Then I started sprinting as fast as I could, leaping two fresh cowpats and desperately trying to breathe enough of the thin air to keep going.
Within 10 seconds all but one of the 30 children were way in front of me. There was just one smaller one who I thought I might be able to catch up with.
They had warned me the competitive spirit was strong here and it must have rubbed off on me because I have to confess that I do not usually try to beat eight-year-olds at games, but found myself using every bit of energy I could find.
I caught up and crossed the line possibly just in front of him, although to be honest I think it was probably a draw.
I can try blaming the fact that I was carrying a microphone and I am not used to the altitude. Alternatively I can just acknowledge they were really fast.
They enjoyed beating me, and did not seem surprised they had done so.
As I left the coach offered me a few words of consolation. "In this field of children today," he said, "I guarantee you there are gold medallists of the future."
No wonder I could not beat them.
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