A couple of excerpts from a recent interview (originally in Russian for ChessPro) with former world #3 player, Artur Yusupov, which left an impression on me:
Why sport and fitness are important
Every element is important – the pure chess element as well, of course, but not only. It’s a case of increasing the probability of a good performance, which is something many people fail to understand. They think, “Ah! Today I didn’t play any sport but I still won, so I don’t need it”. Or the opposite. “I played sport but lost the game”. And people don’t realise that it’s a question of probability. You can do everything correctly and increase the probability of winning by some percentage, but it’s never going to be 100%. Surprises can’t be ruled out. You can, of course, do everything correctly and lose, or everything wrongly and win, but the person who does everything correctly will win more often. You can’t argue with the statistics, and that’s the big difference. Those who fail to follow a sporting regime can be very talented and win individual events, but over a long period of time they’ll do worse than the professionals, and that’s the whole point. When I went on all my runs before important tournaments I thought: “I’ll suffer now, but in the tournament I’ll pick up an extra half point!
On how wins aren't always the result of our brilliant play
A win is always the “achievement” of our opponents. I understood that very well when analysing my old games. I’d naively thought that I outplayed my opponents, but a closer analysis with the help of the computer showed: nothing of the sort! Basically my opponents had even understood the position better than I did and they played well (laughs), but at some decisive moment, perhaps, they lacked energy. They committed a bad mistake which altered the logical course of the game. Analysis showed a totally different picture. So you always win due to the mistakes of the guy sitting opposite. It’s simply not possible otherwise.