Sprinters are fast twitch, long distance runners are slow twitch, you can only improve cardio with drugs to a point, and its all about body types, if tyrone woodley didnt lift a weight in his life, he'd still be more jacked than the wast majority of guys walking around, ngannou has amazing genetic response to drugs, he was a skinny african kid that worked in a mine his whole life, the africsn part has nothing to do with it, not everyone in africa is starving, if he worke a physical job like that, he ate fine