facts and reason wrote:
No amount of training will turn a 5-foot-9 guy into a 7-foot-tall guy.
We can all agree that genetics can provide an advantage, but at the same time we can all agree that hard training is required to reach the full potential in ourselves.
The controversy seems to be only about the degree in which genetics helps.
Obviously a cheetah is faster than a housecat. It makes sense that some humans will be faster based on genetics alone.
You made two important points:
There are people who are much taller than others, due to genetics. Similarly, there are those with a lot more fast-twitch muscles and those with ST muscles. Also IQ varies a lot.
So it's safe to say, that just like there are tall and small people, there are people who have physical traits good for running.
- Some have longer legs in comparison to their torso
- Some have the ability to pump more blood and use a lot more oxygen at others. In other words - some have an untrained VO2MAX of 30, and others of 70. Some have a trained VO2MAX of 55, and others of 85.
- Some have better/more robust bones and can withstand more pounding without getting stress fractures
- Some are mentally stronger, and really able to push to their limits whereas others give out at the smallest amount of discomfort.
So in that point you are right - there are significant genetic differences.
The "cheetah is faster than a cat" is a terrible example on the other hand. You are comparing two different species (yes they are related to the bigger group of "cats" but there is no such subcategory for humans yet). Of course, the cheetah is a lot faster than a house cat due to genetics. But if you compare 10000 cheetahs, how fast are they all? The best speeds recorded were 70-75 mph. Are there cheetahs that max out of 35 mph? Like a 25 min 5k guy? If there are, they would probably not be able to survive in the wilderness and die. They would be too slow to hunt. So we can assume that most cheetahs will have a top speed of around 70 mph, give or take a few. But they all grow up the same way, "train" the same, eat the same, and live similar lifestyles. In humans, you get some people unable to break 25 min in the 5k and others running sub 13. So there must be something more than just genetics that prevents humans from being rather homogeneous in athletic performance.