A friend of Guo, Liu Dan, 38, who was also a professional surfer, agrees, adding that surfing enables her to isolate her from others and to talk to her inner self.

She has also found that the sport has got her closer to the sea, wildlife and nature as a whole, reducing her desire for material wealth, she says.

The Hubei native is now living in Houhai village, Sanya, where she runs a vegan restaurant, enjoys a Spartan and eco-friendly lifestyle and regularly organizes litter cleanups of the beach.

Most of those who take up surfing become ardent environmentalists because they are eager to surf in clean water, she says.

"When you ride waves you feel as though you are communicating with the sea, and before you can forge a harmonious relationship with the ocean you need to learn more about it and the animals that live in it."

With that aim in mind she has done scuba diving courses and learned a lot about marine creatures, and from 2015 she worked for a Malaysian film production company that was making ocean-protection-themed videos and having Chinese subtitles added to them.

"It would be great if more Chinese people see these videos and become aware of the importance of protecting the ocean and living a sustainable life," she says.

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