A common training approach for eastern europe gymnastics is to take a bunch of 5 year old kids, train them all the same. Whomever is left standing at 13 gets to compete in international meets.
After 10 years of boxing, I can give a fun round or two even to people prepping for olympic tryouts (I’ve tried). But a talented 14 year old kid training to go pro in a few years ... they smoke me every time. Even my fully developed adult musculature and the years of ring experience can’t compete with their level of focus and talent. I look like a fool every time.
> with enough proper training the difference between two trained professionals is very, very small
At the extreme ends of elite competition everyone works ridiculously hard. Everyone has the perfect nutrition and the training and the coaches and so on. When the difference between olympic silver and gold in swimming is the length of a knuckle ... either we’re seeing random probabilities playing out (the competition is within margin of error for the test), or it’s genetics.
What else could it be?