There's a pretty big difference between athletes and school children and what fitness training and what long hours of math crunching do to your body and mind.
Yeah? What does math crunching do to your body and mind?
Chess players sit down and think very hard about how moving a rook now could affect the game five-six moves from now. No one actually cares about chess pieces outside of... well, chess players, and there's no real life constraint on moving only diagonally or only one square in any direction. Would you say chess has negative effects on one's life?
