The diving reflex is a clever physiological mechanism enabling the body to manage and tolerate a lower level of oxygen.
Pearson College Marine Science, Tiny Fox Lab

Humans and other mammals have a Diving Response (also known as The Mammalian Dive Response/Reflex) consisting of a set of reflexes that are activated when our face is cooled (such as by the water during a dive) or if we hold our breath. The diving reflex is a clever physiological mechanism enabling the body to manage and tolerate a lower level of oxygen. – Tiny Fox Lab Facts

Preview photo credit: Pearson College Marine Science
Source: en.wikipedia.org/wiki/D…