I read the book, “Running with the Kenyans: Passion, Adventure, and the Secrets of the Fastest People on Earth.” and I would highly recommend reading the book at any level of running. It is very inspiring and gives a window of how and why the Kenyans are such great runners. I always find it inspiring to see the lead back come by when watching a race and typically there are a number of Kenyans in the lead pack.
Why such great runners?
I found this article in the Atlantic which talks about the genes and the culture