To play the devil's advocate, if you extend the argument the parent commenter makes, you could say that a Canadian sprinter has a lower potential because the __

To play the devil's advocate, if you extend the argument the parent commenter makes, you could say that a Canadian sprinter has a lower potential because the ______ ethnic sprinter has a higher percentage of faster-twitch muscle due to genetics. The Canadian sprinter could work as hard has he can but never reach the theoretical limit of the _____ ethnic sprinter. The same argument can be made for VO2 max, armspan, leg stride, etc. Note that I'm not actually advocating for a combined male/female competition nor a split based on genetic potentials.