In deep water, free divers' heart rates fall as low as seals

10 Amazing Freediving Facts

The world's best free divers can drop their heart rate to 11bpm

Research shows that skilled divers who dive without oxygen can tolerate a drop in heart rate of '11 times a minute' - GIGAZINE

How diving seals plan ahead to save oxygen – new research

Exercise at depth alters bradycardia and incidence of cardiac anomalies in deep-diving marine mammals

International : News : The Hankyoreh

In deep water, free divers' heart rates fall as low as seals', international research team reveals

Frontiers A Physio-Logging Journey: Heart Rates of the Emperor Penguin and Blue Whale

Deep-diving 'sea nomads' have evolved an internal scuba tank

Elite freedivers have brain oxygen levels lower than seals

Elephant seals sleep underwater for only two hours per day •

Free divers' heart rates can drop as low as 11 beats per minute

What are the dangers of free diving to 10 metres? - Quora

Indigenous Bajau People Evolved Larger Spleens for Free-Diving, Genetics