The practice in swimming of breath holding can be deadly. Sadly, breath holding has now become a focus in the aquatics world. Even Michael Phelps is promoting shallow water blackout prevention or more simply, breath holding. 

In my last few months here, I have received a couple of complaints from patrons about the lifeguards getting after them for breath holding, and how they won't drown because they know how to swim. What people don't understand is shallow water blackout has nothing to do with your swimming ability. In fact, a majority of the people who die from shallow water blackout are great swimmers and athletes. It has more to do with the chemistry your body is going through while you are swimming and holding your breath.

Shallow water blackout works like this: 

1. You begin by trying to hyperventilate yourself or expanding your lungs. 
2. As your breath holding begins, your oxygen levels begin to drop, your carbon dioxide levels increase and your body begins to become starved for oxygen. 
3. Normally, when your carbon dioxide levels are low, you would take a breath, but since you hyperventilated yourself before going in, your carbon dioxide levels are already high. But you push yourself to hold your breath longer and become unconscious.
4. Once unconscious, your body naturally goes to take a breath, but since you are under water, that causes your lungs to take in water. And without immediate detection, drowning is certain.

Now understand, no one is saying 'don't hold your breath!' shallow water blackout prevention is asking that you do not ignore your need to take a breath. Breath holding is a dangerous practice and you may be putting yourself at an additional risk without knowing it. 

Like a lot of risky practices that take place in and around the pool, shallow water blackout is 100% preventable. 

For more information on Shallow Water Blackout, checkout Shallow Water Blackout Prevention.