I would say it’s always possible to have a mutation that makes endurance harder for you, but it should also be possible to train to improve from the case where

I would say it’s always possible to have a mutation that makes endurance harder for you, but it should also be possible to train to improve from the case where you do no cardio at all. As far as genes you can look at Kenyan and Ethiopian runners for an example of what genetics may do. There has not been a study that has found any single gene that gives them endurance, but the statistics are convincing that there must be some edge there. >The statistics are hard to ignore. This medium-size country of 41 million dominates the world in competitive running. Pick any long-distance race. You'll often find that up to about 70 or 80 percent of its winners since the late 1980s, when East African nutrition and technology started catching up with the West, have been from Kenya. Since 1988, for example, 20 of the 25 first-place men in the Boston Marathon have been Kenyan. Kenyan women appear to have had a later start, winning none of marathons before 2000 (possibly due to discriminatory laws and a tradition of forcing girls into marriages, both of which were partially rolled back by 1990s reforms) and 9 of 13 since then. Of the top 25 male record holders for the 3000-meter steeplechase, 18 are Kenyan. Seven of the last 8 London marathons were won by Kenyans, and the sole outlier was from neighboring Ethiopia*. Their record in the Olympic men's marathon is more uneven, having placed in the top three in only four of the last six races. Still, not bad for one country. And even more amazing is that three-fourths of the Kenyan champions come from an ethnic minority of 4.4. million, or 0.06% of global population. https://www.theatlantic.com/international/archive/2012/04/why-kenyans-make-such-great-runners-a-story-of-genes-and-cultures/256015/ https://www.theatlantic.com/international/archive/2012/04/wh...