Ethios Ethos wrote:
That is just his natural stride.
Did you read the article?
"120 pounds (1.60/54), the unique power dynamics of Bekele’s’s stride was refined by his early career mentor the late Woldemeskel Kostre.
The national team coach worked meticulously with Bekele and a long list of Ethiopian medalists on sustaining a sprint stride where the trail-leg foot is fully inverted 180 degrees from the running surface.
Kostre went on to explain that most runners invert 140-150 degrees and that 180 adds about 50% more torque to the forward leg whip of the subsequent stride. He also added that Bekele was so strong that he could invert his stride not only in the sprint, but for the full 10,000 meters.
Looking closely at Bekele’s stride, the 50% more torque is evident as his leg whip is reminiscent of the torque imparted on Sandy Koufax’s left arm. And in both cases, seemingly unbelievable torque yielded the prospect of career ending injury, especially when that torque is applied endlessly on a concrete-hard track."
I have heard that the Ethiopian training groups emphasize sprint drills, almost daily, so this is not too surprising.