Tanya Streeter spent an incredible three minutes and 38 seconds underwater, with no breathing apparatus or help.
Lungs
When you go that deep under water without an oxygen tank, all sorts of things happen to your body.
Tanya, 30, comes from West Sussex but was born in the Cayman Islands.
'Hard target'
She beat both the men's and women's record for free diving.
"I'm really happy," she said afterwards. "But my greater emotion is relief because I set myself a very hard target with this dive."
Tanya said she had no plans to break the world record again, but she'd wait and see if anyone could beat her.
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