Mariam Shalan is only 17 years old, and is the youngest, professional female free diver in Saudi Arabia. She also holds the Egyptian National record for 50m free diving in the discipline called constant weight.
She started free diving 2 years ago but has been scuba diving since she was 10 years old, so the ocean is familiar territory to her.
Free diving is quite technical. Free divers use terms like breath up, lung squeeze and lung packing. I met Mariam at her home in Jeddah so she could explain what lung packing, breathe up and lung squeeze are.