For a couple of days last month, I ate the same foods as some of the fastest people on the planet — the Kenyans.

I stayed at the same hotel and ate in the same dining room as the Kenya Olympic Marathon team while working on a radio story about how this impoverished nation produces some of the best endurance runners in the world.

The marathoners were training in the celebrated runners' center of Iten in the weeks before their trip to London for the big race today. I can report that their food is bland in the extreme, but then, they're not eating for taste, they're eating for fuel.

Kenya's Kalenjin tribe — you usually find "Kip" in their surname — are legendary at winning medium- and long-distance races. For the past 40 years, they are the reason Kenya has dominated road running more than any other country. There's no secret to their success: They train at high elevation (Iten is 8,000 feet above sea level), which gives them strong hearts and lungs; they start running at early ages (some preteens will run 14 miles a day to and from school); and many are poor. They see winning races as the only escape from rural poverty.

And they eat pretty healthy, as do most Kenyans who have food. As I looked at the lean, quiet, sinewy young men and women sitting down to dinner, I saw plates piled high with carbohydrates.

"It's just normal Kenyan food — vegetables, spaghetti, ugali," said Wilson Kipsang, captain of the Kenyan marathon team.

The national dish, ugali, is a corn mush made from cornmeal and water that has the consistency of mashed potatoes and almost no taste; Kenyans usually sop it into whatever else is on the plate. Githeri is a mixture of boiled corn and kidney beans. Sukuma wiki is chopped boiled kale, which desperately needs Tabasco sauce. The competitive runners seldom eat meat. Beans supply most of their protein. For a snack, the runners eat roasted corn on the cob. No salt.

There are no vitamins or mineral supplements, no special protein drinks or sports drinks pumped full of electrolytes that you might find in Olympic kiosks and every corner store in other countries.

"It is a paleolithic diet," says Dr. Vincent Onywera, senior lecturer at Kenyatta University's Department of Exercise Science. "It borrows heavily from our forefathers who lived on fruits, vegetables, roots and lean meat."

He studied a group of Kenyan runners for two weeks in 2004, for his dissertation, to find out what made them invincible. His conclusion?

"They eat food eaten by ordinary Kenyans. You wouldn't expect an Olympian to eat what they eat. The cook is not a sports dietician, just a woman from the village," he said, chuckling.

Another amazing element of the Kenyan runner's diet is their fluid intake.

One morning, my driver, Joshua Mutuku, and I found a spot beside a dirt road where we could watch the regular morning run. Hundreds of aspiring athletes — and a few world record holders — ran past us with efficient, relaxed strides in their daily 30- to 40-kilometer course along the rust-colored paths surrounding Iten. Not one of them carried a water bottle. At the end of these high-performance runs, they came back and drank tea mixed with raw cow's milk and a bit of sugar.

"They take the milky tea, that is all. It is hard to believe," says Onywera. "This might explain why they compete well. When you see Kenyan runners running the marathon, they rarely take the water." Marathon runners have had a kind of a love-hate relationship with water over the years — some say losing fluids maximizes performance (but drinking for thirst is probably best, science says).

The sight of the Kenyan runners thundering past was so inspiring that, afterwards, Mutuku quietly ducked into a running store in Iten and came out holding a used pair of Nikes.

"I will now start to run," he said, beaming.

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