Sword fighting was something one could get good at (practice) only when using swords was a reasonable way to get something done- Keep the villages in line, collect taxes, storm the bad guys castle. Those days are over.
That leaves you with sword sparring. This either leads us to a sport practice, that is mostly only interested in itself. Or a contrived practice that may hopefully give us some small insight into what sword fighting was.
No human being ever tried to kill another armed man with a sword and considered it practice. No, not even Musashi,