Freedivers explore ocean without scuba gear, on one breath

(CBS News) Husband and wife team Eusebio and Christina Saenz de Santamaria share a love of the water and the extreme sport of freediving.

The sport involves diving down into the ocean, sometimes more than 263 feet, with just one breath of air. They do not use a breathing apparatus or scuba gear; they only use their lungs.

Death-defying free dives push boundaries

Christina can hold her breath for up to six minutes while her husband can hold his breath for eight minutes.

Lungs shrink to the size of oranges when diving to these depths.

Eusebio told "CBS This Morning: Saturday" co-host Vinita Nair that training is all about building up confidence, and it is not about looking at a watch.

Christina recently established a new Australian national record dive of 80 meters, or about 263 feet, which makes her the deepest Australian female freediver in history.

She told Nair that one of the most interesting parts of freediving is that you can interact with animals that you normally would not have the chance to if you were wearing bulky breathing gear.

"One of the main benefits when you're freediving with animals is that you don't have the noisy scuba diving equipment, you don't have bubbles, and you're free to move around the water almost like a fish and the marine animals are really inquisical of you. So, we've had dolphins and sharks and whale sharks come up very, very close to us. This is something we really, really enjoy."

To see pictures from couple's adventures under the ocean visit the couple's freediving collaboration, One Ocean, One Breath.

For Eusebio and Christina Saenz de Santamaria's full interview, watch the video in the player above.