May 7, 2010

How Long Can You Hold Your Breath

Most people find it hard to hold their breath for more than a minute, but Stephane Mifsud held his breath for 11 minutes and 35 seconds last year, setting a new world record for stationary breath-holding, or "static apnoea".

Competitors float face down in a chilled pool to induce the mammalian diving reflex. When your face is submerged in cold water, outer blood vessels constrict, directing blood away from the extremities and towards the heart and brain. Your heart rate slows, reducing the rate at which oxygen is pumped around the body. With training, experienced breath-holders can drop their heart rate by twice that of non-divers upon immersion in cold water.

Hyperventilation before a prolonged breath-hold is also vital. This is because the brain monitors the amount of carbon dioxide in the blood to decide when to trigger the gasp reflex. Of course, having large lungs is a natural advantage.