A breathing technique for snorkeling in which you quickly and deeply breath a few times to lower the concentration of carbon dioxide in your body, hyperventilation allows you to breath hold for a longer than usual period of time. However, when done to excess, the lowered concentration of carbon dioxide fails to stimulate the breath response in the respiratory centre, causing a loss of consciousness due to lack of oxygen. Often occurring on or near the water’s surface, the term “Shallow Water Blackout” is used. As a loss of consciousness in water is clearly dangerous, never hyperventilate to excess. |
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Hyperventilation
