In american-football it's more about muscle endurance than cardiovascular endurance even tho both are involved. But it's still endurance thus yeah you need it.
But needless to say most american-football players wouldn't last half a regular football (soccer) game. They are simply not used to the constant activity. American-football players are used to short burst at full speed and then stop. and when I say stop you completely STOP. No such thing in football (soccer). You're at full speed 3/4 of the time and the time that you are not you're at least at jogging speed. And no substitutions in every other play like american-football either.
First time i watched an american football game i was wondering why they were always substituting players.Plus when offense vs defense are on the field its a completely different set of players so your offense or defense which was already getting a break to breath at the end of every play can now REST on the bench. And these are the "skilled" players I'm referring to like QBs, WRs, DB's and stuff. OLs and DLs and even LBs wouldn't last 5 minutes on a soccer field. Their cardio simply isn't built for it
Basketball and football (soccer) players dont get as many breaks as american-football but the bodies take the pounding that american-football inflicts.
Soccer players and basketball players wouldn't last half a regular football game either, or even a quarter for that matter. It's a different level of training required.





