Although I am an avid chess enthusiast and believe that chess deserves the same respect as any sport, it's still a game, not a sport. The definition of sport is: "an athletic activity requiring skill or physical prowess and often of a competitive nature, as racing, baseball, tennis, golf, bowling, wrestling, boxing, hunting, fishing, etc. ort. The dictionary definition of sport is "
Although this article you linked says that the body has similar reactions to peaks in emotional heights so do near auto accidents, almost falling down stairs and news that a close relative just passed, but none of these would be called a sport.
The dictionary defines game as: "a competitive activity involving skill, chance, or endurance on the part of two or more persons who play according to a set of rules, usually for their own amusement or for that of spectators."
So why not call chess a game and demand equal respect that is given to sports? Why try to make it something it's not?
Just like most chess players can't run a marathon or play professional level football, most professional jocks couldn't endure a marathon chess game and they wouldn't stand a chance against the average club player.
Chess is a great enough game to stand on it's own merits without having to be reclassified into something it is not. It is after all, the King of all games and the game of Kings.
Here is an interesting article stating reasons that chess can be considered a 'sport':
http://www.dispatch.com/live/content/life/stories/2007/09/15/2_CHESS0915.ART_ART_09-15-07_E2_BI7S9AC.html?type=rss&cat=&sid=101
"A four- or five-hour game can leave one physically, as well as mentally, wrung out.", I think this quote is very true. When I play those long games I feel very tired (physically and mentally), just as much as any athlete of a physical sport.