Freediver reveals breath-holding secrets
An international team of scientists has discovered how marine mammals store such vast amounts of oxygen in their muscles.
It is a key adaptation that lets them hold their breath for far longer than humans.
Scientists would now like to find out if their discovery might shed light on how people who can hold their breath for several minutes achieve this feat.
Professional freediver Adam Drzazga explains how he manages to hold his breath for more than six minutes at a time.