Shallow Water Blackout

Freediving’s Most Dangerous Risk (And Infamous Buzzword)

Any initial research into the world freediving will usually result in an immediate warning of the risk of shallow water blackout, and for good reason. As a freediver you face multiple risks when getting into the water with one of the most deadly being the consequences of shallow water blackout. So what is it, and how do you prevent it?

Shallow Water Blackout simply is a loss of consciousness as a result of lack of oxygen to the brain. Freeivers face this issue more than most due to the nature of spending time at depth while holding your breath.

With that being said there are more causative factors at play and to truly understand Shallow Water Blackout it is important to know the role each of them play.

Protecting the airway while training a simulated blackout during a Freediver course.

Medical vocabulary items to review:

Hypoxia- Condition result of decreased oxygen supply to the lungs, blood or tissues

Hypoxemia- Decreased oxygen content in arterial blood

Apoxia- Extreme hypoxia, no oxygen remaining.

Hypercapnia- excessive carbon dioxide in the bloodstream, typically caused by inadequate respiration.

Hyperventilation- Breathing that involves rapid and deep breaths, also known as overbreathing.