How long can you hold your breath?
Science says, without training it's gonna be about a minute.
Lets give it a shot!
Some people, such as freedivers,
can hold their breath for a few minutes, with training.
But scientists have no idea why this is,
or why most of us gasp for air,
long before we turn blue in the face or pass out.
In theory, we should be fine holding our breath,
for much longer.
After all, our lungs can hold about four minutes worth of air.
But at some point our body forces us to inhale.
Researchers call this the "breakpoint".
How does our body force this breakpoint?
Maybe a sensor in our arteries tells our brain
that our blood is getting low on oxygen.
Or perhaps our lungs are warning us they're low on air
and forcing us to inhale.
Science has rejected both of these theories.
We now think it's actually our diaphragm,
signalling our body to take a breath.
Test this out yourself:
next time you hold your breath until you're about to burst,
try relaxing your diaphragm with a partial exhale.
This little trick should help delay your personal breakpoint.
[Phuaa]
Ok - 52 seconds.
That's obviously not going to break any records.
What can we do to hold our breaths longer?
It helps to be relaxed, motivated,
and definitely to be distracted.
Competitive breathholders also get more distance,
when they're submerged in water,
possibly because it slows their metabolism,
or because we don't want to breathe in water.
There are more serious tactics,
such as hyperventillation,
and inhaling high concentrations of oxygen,
but these aren't allowed in most breathholding competitions.
The longest anyone's ever held their breath?
In 2009, French diver Stéphane Mifsud held his breath
for 11 minutes and 35 seconds.
He accomplished this feat floating face-down in water,
and with close supervision.
For Scientific American's Instant Egghead,
I'm Katherine Hermon.