A French man will try to swim across the Pacific Ocean. Ben Lecomte, 51, set off from Japan on Tuesday. It will take him more than six months to finish the 9,000-km swim. He will swim for eight hours a day to get to the west coast of the USA. He will also face many dangers. There will be sharks, jellyfish, storms, rough seas, and very cold water. He will also have to fight exhaustion and any injuries he gets along the way. However, Mr Lecomte said: "The mental part is much more important than the physical. You have to make sure you always think about something positive."
Lecomte trained for six years for this challenge. He has practised every day by swimming in the sea to make sure he is in top physical condition. He also trained his mind. He will be very lonely and he needs to be mentally strong. He is doing the swim to raise awareness of climate change, the effects of plastic rubbish in the ocean, and the effects of the Fukushima nuclear disaster. Scientists will check his body to see how so much exercise affects the heart. In 1998, Lecomte made the first solo trans-Atlantic swim. When he reached dry land, his first words were, "never again".