from the article: "even in an ordinary match game, the average chess professional will sweat away four or five pounds and in a 12 game match no matter how heartily he eats between meetings he will lose at least 15 pounds."
I've also read similar anecdotes about Go masters.
In general I guess no, since most chess players value intellect over physical strength. However, the top guys have to stay fit and exercise to make sure they can cope with the enormous tension during the games.
from the article: "even in an ordinary match game, the average chess professional will sweat away four or five pounds and in a 12 game match no matter how heartily he eats between meetings he will lose at least 15 pounds."
I've also read similar anecdotes about Go masters.