Sumo is Japan’s national sport. Its origins go back more than 1,500 years, and it rarely leaves Japan. But some competitions are starting to tour - including The Grand Sumo Tournament, which recently happened in London. Wrestlers often start training from a very young age, and training is intense. It involves building strength and fitness - and eating. A lot. They consume around 10,000 calories a day.

The BBC’s Mariko Oi is from Japan. She talks us through all we need to know about the sport. We also hear from 21-year-old Aonishiki Arata. He’s one of Ukraine’s top wrestlers and now lives and trains in Japan. And two fans share why they love the sport.

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