There are cultural and social reasons as well. The African s way of living is completely different. It is a struggle to survive. From a young age they have jobs carry their sister or brother, carry water, bring maize home . They have poor conditions and need to work for food just to survive.
Nothing is easy.
Their way of living is key to improving their capacity. They also have mental strength, the strength to come through something. Where Tegla is from, there are maybe 10 girls who have a better capacity, but it is not just the body, it is the brain. She has determination that she will train and be her best. Even, for example, when the Kenyan Amateur Athletic Association did not select her for the world championships several times, she still trained.