Eleven-year-old skateboarder Sky Brown, who is hoping to become Britain's youngest Olympian next year, fractured her skull and broke bones in her left hand after falling from a ramp during a training session in California.
Brown posted a video of the accident on Instagram and reassured supporters that she was doing fine and was going to work even harder when she returns.
"I don't usually post (videos of) my falls or talk about them... but this was my worst fall. I just want everyone to know that it's ok, don't worry, I'm ok," she said.