Chess may not quite fit the classical definition of sport, but I certainly think of it as one.
Like any sport, you train and then go compete against others. It may not be directly physical, but as I'm sure has been pointed out multiple times in this thread, Fischer himself talked about how he would workout and get in shape specifically "for the chess."
You could also train for a spelling bee, an entrance exam, a video game tournament, etc., but those are not sports.
I tend to think of anything that's done on a competitive level as a sport of some kind. So sure, spelling bees, competitive gaming, Magic: The Gathering, poker and chess are all sports to me.
Like I said before, these types of things may not meet the classical definition of the term since they lack a direct athletic component, but that doesn't stop myself (and many others) from thinking of them as sports.
Calling chess merely a "game" doesn't seem accurate. It's a simple game when two people play it in their living room. But once you introduce governing bodies, ratings, tournaments, championships, etc you've turned it into a sport.
If it's not, then we need a new word to describe those things that are done on an organized, competitive level that aren't athletic in nature.
Chess may not quite fit the classical definition of sport, but I certainly think of it as one.
Like any sport, you train and then go compete against others. It may not be directly physical, but as I'm sure has been pointed out multiple times in this thread, Fischer himself talked about how he would workout and get in shape specifically "for the chess."
You could also train for a spelling bee, an entrance exam, a video game tournament, etc., but those are not sports.