Why can't cats run longer distances like dogs?
Cats, both domestic and wild are, for the most part, ambush predators that catch their prey with bursts of speed. Lions and cheetahs do run down their prey, but not over long distances. Wolves chase their prey over long distances, sometimes for hours. This is a classic case of trade-offs. Humans have modified the behavior of domestic cats and dogs, but both still rely on the characteristics of their ancestors. You can build cat muscles with exercise, but you can't make them "dogs".