And now, we briefly
interrupt our critique of the extra silly to salute
someone extra special. Now, if I suggested a sport
that literally drained your body of life sustaining
oxygen, edging you to the very
brink of existence, you'd probably say, no thanks. But then you're not
Alessia Zecchini, aiming to dive
deeper on one breath than any female freediver
has before in her category. [plop] Even at the surface, the average
person runs out of breath after little more than
a minute, but Alessia is f
ar from average. [music playing] And down at 351 feet, almost
the length of a football field, she breaks the record, surfacing after a single breath
hold of 3 and 1/2 minutes. [cheering] It's easy to forget how
dangerous swimming under water can be. It can feel tranquil,
almost womb like, [thud] until you hit a problem,
which in free diving can result in oxygen
starvation, nitrogen narcosis,
decompression sickness, blackout, all the bad stuff. But while I wouldn't advise
trying to beat Alessia's
record, I would
recommend learning the science behind the feat. As our freediver dives, his
body consumes its oxygen supply, which can lead to a
potentially lethal blackout. In his favor is an
evolutionary response called "the mammalian
dive reflex," which diverts oxygen-rich blood to
the vital organs and reduces the heart rate, lowering
oxygen consumption. Efficient monofin
technique also helps. Its large surface area
displaces a lot of water, propelling him forwards
with minimal effort, there
by conserving oxygen. OK, nearly ready to
break some records? It's time for a quick kit check. Flippers work on
the same principle as monofins, displacing
water to generate propulsion. [splash] Not so good on land, though. All right, let's dive down where
the mammalian dive reflex kicks in, even at shallow depths. [music playing] Not exactly what I meant
by mammalian dive reflex. And while they'll still be
experiencing the reflex, they're rather wasting its
oxygen-conserving effects. That's bett
er. Making the most
of the propulsion generated by his flippers
with gentle rhythmic kicks, conserving precious oxygen
for the swim back up, or for riding a bike. OK, let's head up, but calmly
and oxygen efficiently so as to avoid that thing
all free divers fear. I was actually thinking
of "blacking out," but on that evidence,
I think we should leave Alessia's record well alone.
Comments
The average person runs out of breath after a little more than a minute. What did you find most fascinating about the science behind free diving?
I can’t believe this made it to National Geographic’s page... this guy doesn’t sound like he has ever dove
Click bait — poor quality content. Deleting this is a great idea. Do some research with actual freedivers next time.
Sadly, not much is explained here... So let me help: when you dive, the pressure around you (from the water) compresses your lungs as they are filled with air. This compression leads to compression of the gases as well, which makes it easier for the lungs to absorb the remaining oxygen in it. The pressure also compresses the gases that are usually in solution (like nitrogen) in your blood. When you now swim back to the surface too fast, because you feel the need to breathe, your lung rapidly decompresses as the gases expand, making it much harder to extract oxygen. You suddenly have way too little oxygen in your system from the rapid pressure drop, making you fall unconscious (brain and muscle tissue are deprived of oxygen). On top of that, gases that were compressed in your blood, also expand quickly, forming bubbles in your blood that can block blood vessels and lead to infarcts.
Imagine diving and and all of sudden you hear something says: Detecting multiple leviathan class lifeforms in the region. Are you certain whatever you are doing is worth it?
Decompression sickness does not happen in freediving unless you are doing multiple deep dives one after the other. Not enought time to accumulate nitrogen
If the intention was to give information to the public in order to educate and make it safer for people; you missed explaining the part which is the most dangerous.... hyperventilating. Taking big breaths before you hold your breath is literally the most dangerous thing people can do for freediving. No “breath up,” no yogic breathing, no WimHof... that’ll kill you if you mix it with freediving. Tell people not to do this and you’ve done your job. There, now people are safer.
Wow... I was expecting more when I saw the Natgeo logo
This video feels like an early 2000’s discovery channel segment
Freediving is a real discovery. You can feel so much while underwater. Is it dangerous? Yes it is. That is why you have to take a serious course and never do it alone. To say that it is too dangerous and not fascinating: that is stupid!
“flippers” us divers: imma take my gear and head out
Superficial and misleading info about freediving. Really a shame.
This video needed to be fact checked. The guy lists a bunch of dangers that are only present for scuba divers 😂
Lol the way the dude swam into the wall
I remember when discovery channel resonated with knowledge rather than clickbait and silly scripted text.
Free diving seems very fun, but I couldn't try it because I didn't have a chance. I admire the fact that the free diver in the video broke his record. After watching the video, I wanted to give it a try. It was surprising to see the free diver in the video diving across the size of a soccer field while holding his breath. When a beginner diver dives, he learns that oxygen is supplied to his head and delivered to his vital organs.
Just hearing the term free-diving reminds me of Audrey Mestrè & gives me chills. RIP 🙏🏾
The diver wearing the red Incredible suit lol
This is why we bigfoots never go free diving
Nice record.