'Like climbing Mount Everest:' Inside the gruelling world of the Chess World Championship

China's Ding Liren speaks after his victory in the FIDE World Chess Championship in Astana, Kazakhstan, April 30, 2023. (AP Photo/Stanislav Filippov)

Ding Liren slumped over the board with fallen chess pieces scattered in front of him in the moments after he won the Chess World Championship last year.

His head bowed, his expression blank, he seemed as if he was collecting himself after a brutal fight, still reeling from the blows his opponent Ian Nepomniachtchi had landed, wary to move in case his legs gave out under him.

The pair had been dueling each other for three weeks, maintaining a mind-boggling level of concentration during that time, for any momentary lapse could cost them the game.

The Chess World Championship is an extraordinary, singular event. Its first edition was held 138 years ago but, in that time, just 17 players have become world champion. “Chess demands total concentration,” Bobby Fischer, the only American ever to hold the title, once noted, and only those capable of maintaining that focus for weeks on end can achieve the biggest prize in the sport.

“It’s our Mount Olympus,” Viswanathan “Vishy” Anand, a five-time world chess champion, tells CNN Sport. “It’s the thing you spend a lot of time trying to achieve, aiming for, dreaming of, since you learned the game. It’s like climbing Mount Everest or crossing the Amazon.”

On Monday, this year’s edition of the grueling tournament will begin in Singapore with China’s Ding seeking to defend his title against India’s Gukesh Dommaraju, better known as Gukesh D, who is still just 18 years old and could become the youngest ever person to be crowned world champion.

“You lose weight during a chess tournament of this intensity. The pressure is absolutely enormous,” Malcolm Pein, chess correspondent for English newspaper The Daily Telegraph, tells CNN Sport.

“A lot of the time, it comes down to exhaustion. Players are very well-matched, very prepared. It’s very hard to get an advantage, but sooner or later somebody becomes tired and that might make them make a mistake.”

Even now, with the tournament shorn of Magnus Carlsen – the world’s best player who is sitting out his second world championship – and the increasing popularity of the shorter rapid and blitz formats of the game, becoming chess world champion is an accolade that still transcends the sport.

But the buildup to this tournament has been unlike any other since Ding has struggled with personal difficulties and mental health challenges after his win, taking an extended break from chess to focus on his mental health. Now, he “is not so bad, not so good,” he told chess YouTube channel “Take Take Take,” and sees himself as the “underdog” going into this tournament.

'Tossing and turning'

A long history of epic world championships and rivalries looms over both Ding and Gukesh. Most famously, Garry Kasparov and Anatoly Karpov faced off for five months across 48 games of chess at the 1984 tournament as they sought to reach the six victories that would crown them world champion.

Karpov had taken a seemingly unassailable 5-0 lead early on, but Kasparov clawed his way back, winning the 32nd, 47th and 48th game to make it 5-3. He was still behind, but he had all the momentum. Karpov, meanwhile, had lost 22 pounds during the championship as he fought to maintain his lead. Eventually and controversially, the match was called off to preserve the players’ health.

Now, the tournament lasts weeks instead of months, but players must still withstand its immense pressures, each one developing “something habitual in how they compose themselves,” says Danny Rensch, the chief chess officer of Chess.com.

“Some of them have the habit of getting up and not actually spending a lot of time sitting at the board when it’s not their turn … to keep their blood flowing. Some of them do this just because that’s how they deal with the stress and nerves,” Rensch tells CNN Sport, adding that others sit at the board locked in the same position.

Chess is a game that takes place almost entirely within a player’s mind, their calculations and machinations visible only to a skilled viewer predicting the next move. Several questions are running through a chess player’s head when an opponent makes a move, says Pein, rattling them off.

“The first thing you do when your opponent makes a move is you say to yourself, ‘Why did they make that move? What’s changed on the board? Is there a threat? And is there a threat to my position from this move directly? And who do I think stands better, and why …. How long do I want to think about my reply? And then also, am I playing for a win? Am I trying to save this position, or is there no way to avoid a draw?’”

These games and calculations can go on for hours at a time; in 2021, Carlsen took seven hours and 47 minutes to defeat Nepomniachtchi in one game on his way to his fifth world title.

So in between games, sleep is “the most important thing,” says Vishy, though it has to be a deep sleep where “you’re not thinking about the game, you’re actually resting.

“There’s no point tossing and turning … because you either can’t get the previous game out of your head or you’re worried about the next one … I used to go the gym very often right before sleep, so I was exhausted enough to fall asleep.”

Although the players are barely moving compared to other sports, the huge amounts of brainpower required mean that they must maintain their physical as well as mental fitness.

When Vishy was training in the months before his world championship matches, he would run or cycle for an hour each morning to build up his endurance before turning to chess for six or seven hours a day, working out his opening moves, trying to predict his opponent’s intentions and weaknesses alongside trainers who had previously played in world championships. In more recent years, computers help competitors to prepare, assisting them in analyzing the best move in any given scenario.

“They’re not training for a physical activity,” Rensch says. “They’re training to make sure that they’re in great shape, overall physical fitness, allowing for proper blood flow, and all the things that can help a human being maintain a super high level of concentration for hours at a time.”

Even just qualifying for the match is an epic endeavor. For the right to take on the defending champion, the challenger must first win the Candidates Tournament comprised of the best players in the world, all of whom are there based on their performances at specific tournaments throughout the year.

Before Vishy competed in his first world championship in 1995 against Garry Kasparov, he “had been playing to qualify for the event for five years, so there was a long journey already,” he says.

Qualifying is so difficult that one appearance at a world championship might be all that a chess player can hope for. This shot might be their only one, which in turn adds to the stakes.

“Of all the people who lost a world championship match, it took them a while to recover before they even started playing well again or at their previous level,” Pein says. “It’s such a blow … So it affects people quite badly.”