During the festival of Nakizumo, which literally translates as 'crying baby sumo', wrestlers take a child each, enter the ring, then begin pulling faces and making noises in order to get the babies to cry.
The first child to cry is declared the winner, and if both start crying at the same time, then the champion is the one who cries the loudest. If the babies don't shed tears, laugh or - as sometimes happens - fall asleep, then the referee dons a devil mask to finish the job.
The 400-year-old tradition is based on the proverb 'crying babies grow fastest', and it is believed that making the infants weep will bring good health. It is also thought that the sound of their screams will ward off evil spirits.
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In the 400-year-old festival of Nakizumo, which literally translates as 'crying baby sumo' student sumo wrestlers compete to make children bawl
The wrestlers take a child each into the ring, then pull faces and shout Naki, meaning 'cry', to start the tears flowing. Whoever cries first in the winner
If both babies begin crying at the same time then whoever is the loudest is declared victorious. The competition takes place in the Sensoji temple, Tokyo
The festival is based on the proverb 'crying babies grow fastest' and is designed to bring good health. The sound of screams is also thought to ward off evil spirits
In order to compete in the festival, babies must have been born in the previous year. The competition is held on Children's day in Japan, part of a national holiday
If the babies don't cry, laugh or even fall asleep, then it is up to the referee to get the tears flowing using a traditional oni, or ogre, mask
Good god: Once they begin bawling the babies are held up high so their screams will be closer to heaven which the Japanese believe will strengthen the blessing
The ritual takes place all over Japan but is most commonly performed by student sumos at the Buddhist Sensoji temple in Tokyo
The contest is watched over by a traditional sumo referee called a gyoji, who wears an elaborate silk outfit in order to denote his rank, and holds a wooden fan used to start the bout
The festival is held on April 26th each year and is part of Golden Week, a period of nine official public holidays which lasts from late April until early May
Sumos hold babies while competing to make them cry the fastest during the annual Nakizumo festival held in Sensoji temple, Tokyo, Japan
One baby looks on with a rather sinister scowl as the other child weeps, meaning she is the winner of this round of Nakizumo
In order to take part in the competition, the infants are often dressed up in miniature kimonos, have devil horns put on their head or wear bibs with traditional writing on them
