IN FOCUS CHESS BOXING:BLOODIED, BRUISED and battered, the two boxers have just completed a brutal bout in the ring in Berlin's Mitte district and remove their gloves to face their next challenge: a round of speed chess.

Welcome to the bizarre world of chess boxing, developed in inner-city Berlin and featuring alternate rounds of chess and boxing in a fierce combination of brains and brawn.

Inspired by a science fiction book, the sport that emerged initially as an urban art event has grown into one enjoyed by many across three continents.

Boxers play six rounds of chess alternating with five of boxing as they put both their physical and mental skills to the test.

Chess rounds last a total of four minutes, with the players wearing headphones to block out cheers, coaches’ advice and the commentator’s voice.

“This is all about discipline and control of your body and your mind,” said the sport’s founder, Iepe Rubingh, a Dutchman who set up the first club in Berlin.

Rubingh, a chess-playing artist, took up boxing in his 20s. It was around that time that he stumbled across the work of graphic artist Enki Bilal, whose novel Froid Equateurfirst featured the sport.

“I started quite late with boxing training. I thought about this sport and said: ‘This cannot be done. You cannot play chess after a round of boxing. You are just not capable, your body will not allow you’,” he added.

With huge amounts of adrenalin pumped into the body during the fight, a heart rate of 170 and more oxygen in the muscles than in the brain, chess boxers’ limits are really tested when they take off their gloves and sit down, sweaty and out of breath, at the chess board.

“When you sit down to play chess after your boxing round then you look at the board as if it is the first time you see it,” said Rubingh. “It is a bit like biathlon, with the skiing and shooting.

“Adrenalin is massive, making it difficult to think straight, and it also makes you fearless and that is the biggest mistake you can make on the chess board at that time. You have to train hard for this changeover.”

Chess boxers have little in common with the stereotype of a prize fighter, or a chess player for that matter. Many of them are 30 or older and are in top physical condition, with a high intelligence quotient (IQ) and a rating under the Elo system used by the World Chess Federation (FIDE).

Berlin police officer Frank Stoldt is one of them. Long a kickboxer, the 40-year-old Stoldt, who has an Elo chess rating of 2,000, joined the Berlin chess boxing club the moment he heard about it.

“I thought they had invented the sport for me,” said Stoldt, interrupting a round of speed chess in a small training room in the Berlin gym.

“It is a unique sport, combining two seemingly opposite things. But it has huge potential. It is this testing of the human body and mind that makes it so exciting,” adds Stoldt, a former chess boxing world champion, before taking up his skipping rope for a cardiovascular workout.

Some have called chess boxers the ultimate fighters, excelling in both physical and mental bouts. Winners in each of the four weight categories can be declared by a knockout or a checkmate, or when playing time runs out.

The sport has grown beyond Germany to Russia, the United States, England and Australia. So far, only men’s competitions have been organised but a small number of women are now training at chess boxing clubs.

Losing its main sponsor due to the economic crisis has done little to dampen the sport’s expansion plans, it seems.

A European championship fight in England in October will be followed by the world championship in Russia’s Siberian city of Krasnoyarsk.

“Grass-roots level development is what we are doing right now and we can do that easily,” said Rubingh.

“We do not need to organise a congress for 100 people like other federations. “We just need an (online) group on Facebook,” said Rubingh, during a tour of the visiting athletes’ Berlin accommodation where the rooms were covered with wallpaper showing chess boxing scenes and sprinkled with quotes from famous boxers and chess players.

Eastern Europe, and Russia in particular, have proved to be fertile ground for the sport with both boxing and chess widely played.

“Russia is the chess boxing nation and it is now waking up,” added Rubingh.

One of his plans is to stage an unofficial demonstration of chess boxing during the 2012 London Olympics.

“We are planning some guerrilla shows in London during the Games,” said Rubingh, who as an artist has blocked off roads in Tokyo and Berlin, causing traffic chaos.

“Our vision is to one day make it to the Olympics. I think there it would become the top discipline for the ultimate athlete.”