Taekwondo is a professional sport in North Korea, a highly militaristic society
One by one the North Koreans approached the board, yelled for inspiration and struck out, trying to split the interlocking plates with fist, hand or foot -– then reeled away in pain.
"Taekwondo is the spirit of our nation," said Rim Wi Sok, 26, who won the 71 kilogramme fighting category at the Mangyongdae Prize martial arts competition.
The event, held as part of the celebrations for the anniversary of the 1912 birth of the North's founder Kim Il Sung and named after his birthplace, is the country's national taekwondo championship.
Taekwondo is a professional sport in the North, which is a highly militaristic society. Kim's son and successor Kim Jong Il -– father of the current leader Kim Jong Un –- developed a Songun, or "military first" ideology, prioritising the needs of the armed forces.
Taekwondo fighters train full-time for provincial teams and dominate their code's version of the world championships.
But they do not take part in the Olympics: the sport has been riven by politically-driven schisms, and the International Olympic Committee recognises a rival governing body based in the South, World Taekwondo –- which in 2017 dropped the word Federation from its name, ending the unfortunate acronym WTF.
The sport was developed and codified by South Korean general Choi Hong-hi, who amalgamated Korean and Asian martial arts, with an emphasis on mental discipline, into what he called taekwondo –- the art of the hand and the foot.
But after falling out with the South's military-backed dictator Park Chung-hee he went into self-imposed exile and later became a frequent visitor to Pyongyang, where he died in 2002.
Even so, 'Yikyora!' –- translated as 'Fight!' in the North -- is a cry of encouragement on both sides of the Demilitarized Zone that divides the peninsula.
In the breaking event, the boards have to be hit with sufficient force and exactly in the middle, both horizontally and vertically, to split them apart, explained a guide at the Taekwon-do Hall in Pyongyang, making it a test of precision as well as power.
Anything else and they will stay together, and failure -– which appeared to be the more common outcome at the contest -– is even more painful than success.
After their attempts the athletes limped away or inspected the damage to their callused hands, their knuckles swollen from years of punching the plastic target, trying to hide the agony throbbing through their limbs.
"It hurts," said Rim, from Pyongyang. "If you train regularly it hurts a bit, but if you try to break the boards without regular training it hurts a lot."
He does not visualise the board as an enemy, he told AFP.
"If a player is mentally ready to break the board at any cost, his hand will be more powerful."