Sara Campbell - Extreme Diving Super Human Challenge


Sara Campbell - Extreme Diving

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In my quest to find real-life superhumans,

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I've taken to the depths.

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Human beings like you and me are able to explore this amazing

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underwater world using breathing equipment, like this scuba gear.

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But imagine being able to be down here for minutes at a time

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without any breathing equipment at all.

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You'd need incredible abilities underwater - huge lungs,

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amazing swimming skills, fish-like streamlining.

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You'd need the powers of a real-life superhero,

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a superhero like Aquagirl,

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perfectly at home underwater,

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and with unbelievable swimming ability.

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Well, I've heard of a real-life Aquagirl.

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Sara Campbell is one of the world's greatest freedivers.

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With just one breath, Sara can dive to crushing depths

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few ordinary humans could survive.

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She's broken four world records,

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and won the Freediving World Championships.

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Freediving is what we call diving underwater

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without any special breathing equipment, for example, scuba gear.

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With the right training and experience,

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freedivers can dive very, very deep.

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But without the right training and supervision,

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it can be very, very dangerous.

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Tim has travelled all the way to Dubai to meet this superhuman.

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And here she is, Sara.

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-How amazing to meet you, hi.

-Hi, lovely to meet you too.

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Now, tell me, what is the longest you've ever held your breath?

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Me personally? Just over five minutes,

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which, to the average person, it sounds like a big number.

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That's amazing. What is the attraction for you

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of not wearing scuba gear?

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The freedom of how I can move in the water, and then also the challenge.

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You know, scuba is not really a sport, whereas freediving,

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learning to hold your breath, pushing your body...

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Every time I jump in the water, it's like I'm learning about myself

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and learning really what's possible. So far, I haven't found the limit.

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With scuba diving, there's a depth which you can get to, basically,

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-but you're going below that, are you?

-Yes, I dive a lot deeper than

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-most scuba divers.

-Wow, right, wow.

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You have the most incredible abilities.

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We would love to put you to the test.

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We've set up three Super Tests designed to help us examine you

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and to try and help us understand what makes you unique.

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We've searched high and low to find somebody to measure up

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against you, but we couldn't find anyone.

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So I'm going to have to do. Is that OK?

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-That sounds brilliant.

-OK, let's go.

-Let's go.

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This is Dr Megan John. She's an expedition doctor

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and has kept people alive while they attempt some of the most

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dangerous activities you can imagine.

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She's created three Super Tests to find out how Tim

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and Sara's bodies react differently.

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For Super Test One, I've brought the two of you here

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to the Ambassador Lagoon, Dubai. Because here,

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-they've got one of the biggest aquariums in the world.

-Wow.

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In my Super Test One, you'll both be wearing scuba equipment.

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I'm going to be looking at how long you can each make

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the air in a tank last you.

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Inside this tank, there are 60,000 fish.

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Are you two ready to take the plunge and join them?

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-I can't wait.

-Are there sharks?

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-Wait and see.

-OK. This is brilliant!

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Scuba diving is different from freediving.

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Scuba divers breathe underwater using tanks full of air,

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which get used up during the dive.

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Sara and Tim will be using scuba tanks in Super Test One,

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so Dr Megan can measure how much air they use while they swim about.

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It's important they don't stop to admire the fish, though,

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so Dr Megan has organised a game that they have to play.

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She's hidden 20 coloured marbles in the fish tank. Sara has to find

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the ten yellow ones, and Tim the ten red ones,

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and they have to put them in a tray to get counted.

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So, Sara, do you have any tips that might help me?

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Yes, absolutely. The most important thing when you're in the water,

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whether it's freediving or scuba diving, is to remain calm.

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And the way that we remain calm,

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the best way is to manage how we breathe.

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Make sure that you keep it calm, keep it slow, relatively deep.

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If you find that you're breathing very shallowly and rapidly,

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that means that you're getting into a panic state and that is going to

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have an effect, not only on keeping your mind nice and calm, so stopping

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you getting too excited while you're looking for those marbles,

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but it's also going to keep your heartrate low, which means

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you're going to use less of the air in your tank as you swim around.

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Oh, right, so not only does it stop me from getting panicky,

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-it also helps me to save air.

-Yes.

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Very clever. So long, slow, deep breaths

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Yes, absolutely.

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Long, slow, deep breaths? Easier said than done.

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Once Sara and Tim start looking for the marbles in Super Test One,

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there's a good chance they'll forget all about their breathing.

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Sara, Tim. I've set you both up with tanks filled with identical

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amounts of air, 200 bar. They've each got a gauge

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which will start at 200,

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and the needle will go down as you use up the air inside.

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Don't worry, I've made sure there's more than enough in each tank

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to last you both 20 minutes.

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You've also got these specially adapted masks, which will

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allow you to talk to me while you do the challenge.

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-But I would suggest you don't talk too much.

-Cos it uses lots of air.

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-Exactly.

-So, like, "Wow, a fish! Wow, a marble! Wow, a thing!

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"Wow, this!" would not be good.

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-There's 60,000 fish down there.

-That would take a lot of air.

-That would.

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Scuba diving can be very dangerous,

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and even experienced scuba divers can get into difficult situations.

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Diving deeper can cause you to sink faster

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and not knowing how to get back to the surface can cause you to panic.

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Panic causes you to use more oxygen, meaning the air level

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in your tank will start to drop faster.

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If you try to swim to the surface too quickly, the change

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in water pressure can cause earache and your ears could start to bleed.

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You may get decompression sickness.

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Decompression sickness can cause sore joints and breathing problems.

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In severe cases, it can cause dizziness, confusion,

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unconsciousness and death.

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To make sure Sara and Tim are as safe as possible

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during Super Test One, they've had training beforehand,

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and a team of safety divers will be in the water with them at all times.

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OK, then, guys. You get your kit on.

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I'm going to head down to the observation window.

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When you're ready, you head over there

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and I'll give you a cue on the walkie-talkie. OK?

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-Yep. Ready?

-Good luck.

-Brilliant, let's do this.

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Sara doesn't normally use scuba gear.

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With her freediving abilities, she doesn't need it.

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But by using it today, Dr Megan can see how much air

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her and Tim use during the 20-minute test.

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OK, then, guys, are you ready?

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Three, two, one, dive!

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It's a massive tank, full of moving fish.

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How on earth are they going to find any marbles?

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I did notice that some of the fish have been pushing

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the marbles around - that could make it even harder for them.

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Sara and Tim are trying to stay relaxed

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and swim as efficiently as possible in this test,

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just like a freediver has to

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when trying to make one breath of air last.

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It's interesting, Sara's body language,

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keeping her arms very still.

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It'll be interesting when Tim comes back round

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to see how he's managing.

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Early in the test, and Tim seems to be doing quite well,

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keeping relaxed while he swims around.

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So they've not found any yet.

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Nearly four minutes.

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At the end of the 20-minute test,

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Dr Megan will read the gauges in their tanks

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to see how well they've managed to make their air last.

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I've got one, hurray!

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Oh! I've found my first one too.

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There we go. Sara, the first marble in the basket.

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Tim's got one too.

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Just seconds apart.

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This is a great way of testing how the guys use their air.

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Because it's very distracting - this is a competition,

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this is a game for them, so they can't think about just technique.

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Yeah, that's my second.

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There we go, Sara's coming in with her second now.

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Ha-ha, look at that!

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5 minutes and 30 seconds.

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I have lost my marbles.

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Number three, so three to one. Nearly seven minutes.

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Remember, I'm not interested, really,

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in how many marbles they get.

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I'm using that as a distraction to keep them both swimming

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so I can record how much air they use in the 20 minutes.

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The more Tim and Sara move round, the more oxygen they'll use up.

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This is because everything in your body is made up of tiny cells.

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There are lots of different types of cells - skin cells,

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muscle cells, nerve cells, and even bone cells.

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Every single cell needs oxygen and sugars from your body

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to work properly.

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They use the oxygen and sugars in a chemical reaction

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to make energy, and this is called respiration.

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Respiration also makes water and another gas called carbon dioxide.

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You don't NEED carbon dioxide, so you get rid of it when you breathe out.

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The harder your cells work, the more oxygen they need

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and the more oxygen you breathe in.

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Sara's doing well not getting stressed out,

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considering where some of the marbles have been hidden.

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I've found another ball, but it's in here.

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I don't know if my arms are long enough to get it.

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If I were freediving now, I could get inside here easily.

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But with all this breathing equipment, I can't.

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Tim is struggling to keep his breathing under control.

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It's really hard down here to try

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and concentrate on breathing slowly. Way overexcited.

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And the more excited Tim is,

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the more oxygen his body will be demanding.

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Oxygen gets into your body through your lungs.

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Your lungs are made of lots of tubes that branch out like a tree.

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At the end of the tubes are tiny air sacs called alveoli.

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The average human body has 700 million alveoli,

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and if they were all laid flat, they'd cover half a tennis court.

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When you breathe in, air goes right down into the alveoli.

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Alveoli are covered in blood vessels, and oxygen from the air goes through

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the walls of the alveoli into your blood to be carried round your body.

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The faster you breathe, the more

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oxygen your lungs will take in from the air.

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I just found two.

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Sara's just showing the cameraman she's got two marbles in her hands.

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I wonder if Tim noticed.

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Sara's got another one there, look, I can see that.

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I really have no idea where they are.

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So that's five marbles to Sara, three to Tim...

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..at 13 minutes and 45 seconds.

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A big part of Sara's amazing ability as a freediver

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is keeping calm whilst diving.

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In general, watching Sara is more peaceful, she's more relaxed,

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she moves a lot less and she doesn't use her arms at all.

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With all his flapping about in the water,

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Tim must be using more air than Sara.

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As the time goes on, they both seem to be working harder.

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So that's five marbles for Sara, four for Tim,

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with three minutes to go.

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What's really important is not how many marbles they get,

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but how much air they've used by the end of the test.

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Obviously, we know that Sara is much more experienced in the water

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and much more comfortable in the water than Tim is.

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Because of that, she's using a lot less movement,

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she's more confident. And Sara's coming in with another one.

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That's 20 minutes. If you can both finish now.

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The two of them are heading back up to the surface.

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I want to find out how much air they've both used.

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With the test over, Sara's right to look happy.

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I'm OK!

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She collected six marbles while Tim only had five.

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Fresh air!

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But it's not the marbles they've collected that's important.

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Good, you're out.

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It's how much air they used.

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And Dr Megan's looking at the results now.

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Tim, during the 20 minutes, you used up 110 bar of air.

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But, Sara, I'm completely blown away.

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You only used 60 bars of air.

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You would have been able to last almost double

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the length of time that Tim did.

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I know you're a bit smaller than Tim, so I might have expected him

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to use a LITTLE bit more, but that difference is phenomenal.

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I used up a lot of air searching for marbles,

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but long ago in the Middle East, people searched the ocean floor

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for a different prize, using just one breath.

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For hundreds of years, diving for pearls was a popular job in Dubai.

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Pearl divers would freedive up to as 40m down to the seabed

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to collect oysters which make pearls.

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The divers collected as many oysters in one dive as they could,

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holding their breath for up to five minutes at a time.

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When they ran out of air, they'd tug on a rope

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and be pulled to the surface.

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They dived all day, risking their lives among poisonous jellyfish

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and sharks for the valuable pearls.

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Freediving has always existed.

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Many cultures around the world

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have relied on swimming while holding their breath to find food,

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long before scuba-diving equipment was ever thought of.

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Most mammals can dive for brief periods under water. In fact,

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some mammals went from spending a short time underwater

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to living full-time there.

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Sara's a world champion, and with all her training,

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she can hold her breath for around five minutes underwater. Amazing.

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But some mammals, like whales, can dive for 90 minutes

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on just one huge breathe.

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All mammals have a special trick that lets them dive

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so well underwater. It's called the mammalian dive reflex,

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and it starts as soon as your face hits the water.

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Most people can hold their breath for a short while,

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but underwater, you can hold your breath for a bit longer.

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This is because nerve cells on your face send information

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to your brain, telling it that you're underwater.

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Your brain then sends signals round your body.

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This causes less blood to flow to your arms and legs

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so they use less oxygen, and your heartrate slows down.

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Using less oxygen means that the air in your lungs will last longer

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and this means you can hold your breath for a bit longer.

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With years of training, this automatic dive reflex helps

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top freedivers, but it will not save the average human from drowning

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if they run out of air.

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You must never fight your body's natural need to breathe.

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You really could drown.

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To be able to be a great freediver like Sara, you need to be able

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to stay under the water for as long as possible.

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To do this really well, you'll need to take as much air as possible

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down with you in your lungs.

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In Super Test Two, I want to look at how much air

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you can hold in your lungs. I'm going to do that using a spirometer.

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How does it work?

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Well, I'll be asking the two of you to take a deep breathe in,

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and then out and back in again though the tube.

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The computer will then give me a readout about the total amount

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of air you can fit into your lungs.

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-Great.

-Shall we try it?

-Yeah, let's have a go.

-OK.

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-Right then, Tim, you're up first.

-OK.

-When you're ready.

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Tim's filling his lungs with as much air as he can.

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Breathing right out...

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Whoa, Tim, don't hurt yourself.

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Don't forget to breathe back in again.

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The machine can now measure how much his lungs can hold

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compared with the average man of his size.

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-Let's have a look.

-Did that work?

-You went purple.

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-Did I?

-Yes.

-I tried really hard.

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You might think that it's your lungs

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that make you breathe in and out, but it's not.

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It's done by a very clever muscle.

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Your diaphragm is a stretchy muscle

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that sits right underneath your lungs.

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When it moves down, it pulls air into your lungs

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and when it moves up, it pushes air out of your lungs.

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Your brain controls your diaphragm, making it move 12 times every minute.

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When you're breathing at rest, you will only fill around a quarter

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of your lungs with air.

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But if you pull your diaphragm as low as you can,

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you can fill your lungs completely with air.

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The maximum amount your lungs hold is called your lung capacity.

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With training, you can make your lung capacity bigger.

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-OK, Sara, you're up next. When you're ready.

-Yep.

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A deep, controlled breath from Sara.

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She looks like she knows what she's doing.

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That's amazing, you actually become a square.

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You know, like normally, you're a normal person-shape

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and then suddenly you go... and you inflate yourself.

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-You inflate yourself.

-I'm a pufferfish.

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Now, Tim, you did better than I expected.

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-10% better than average.

-OK.

-Really well done.

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Thanks. That's really exciting.

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Sara, however, you achieved 3.82 litres.

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That's over 22% more than we would have expected for your size.

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Phenomenal.

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With an incredible 22% more than the average lung capacity,

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Sara has a lot of breath to use during a dive.

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It's no wonder she's one of the best freedivers in the world.

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So, how does Sara do it?

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Sara's lungs might not be bigger than the average person,

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but years of training have made her diaphragm superstrong, so Sara can

0:18:530:18:57

stretch her lungs to make them even bigger and hold even more oxygen.

0:18:570:19:02

Sara uses mental exercises to keep herself calm and relaxed,

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and moves as little as she can.

0:19:060:19:08

This slows down her heartrate and uses less oxygen.

0:19:080:19:10

Sara is also quite small,

0:19:100:19:12

and smaller bodies use less oxygen than bigger ones.

0:19:120:19:14

All this means that when Sara dives, not only does she hold more air

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than an average person, but she uses it up more slowly.

0:19:170:19:21

This allows her to dive for a long, long time on just one breath.

0:19:210:19:24

Holding your breath's hard enough when you're relaxed.

0:19:290:19:31

But imagine trying to do it with a shark in the water.

0:19:310:19:34

On Reunion Island near Madagascar, there have been

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so many shark attacks that swimming was banned.

0:19:390:19:42

Luckily, freediver Fred Buyle came to the rescue.

0:19:420:19:46

He can hold his breath calmly at the bottom of the ocean

0:19:460:19:49

without disturbing the sharks.

0:19:490:19:50

Incredibly, when Fred plays music, the sharks come to investigate.

0:19:500:19:55

When they get close, he puts a tracker on them

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without hurting them. Now, people can swim safely

0:19:580:20:01

because lifeguards know exactly where the sharks are.

0:20:010:20:04

For the final Super Test, Dr Megan has taken Sara and Tim

0:20:090:20:13

off to the coast of Fujairah, in the Gulf of Oman.

0:20:130:20:16

Super Tests One and Two, to control the environment,

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we carried them out in an aquarium.

0:20:190:20:21

But to really see what Sara can do with her freediving,

0:20:210:20:25

I've had to find somewhere a lot deeper - the ocean.

0:20:250:20:29

The team have come to a deep-water location

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and dropped a line an incredible 50 metres down.

0:20:320:20:35

This line will mark the depth and keep Sara and Tim on course.

0:20:350:20:38

With one breath, they will attempt to swim all the way to the bottom

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and return. 100 metres - that's like swimming

0:20:420:20:45

the length of a football pitch with one breath.

0:20:450:20:47

Because it's such a risky challenge that we're undertaking,

0:20:470:20:50

I've put together my largest ever safety team.

0:20:500:20:52

I've got a lot of medical experts here on standby.

0:20:520:20:55

We've got specialist safety scuba divers in the water

0:20:550:20:57

and some specialist safety freedivers.

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If Sara and Tim get into trouble,

0:20:590:21:01

we need to get them out straight away.

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The two of them could black out or sustain pressure injuries.

0:21:030:21:06

One factor that the team hadn't reckoned on was the bad weather.

0:21:060:21:09

There's a strong current today,

0:21:090:21:11

which is dragging the weighted safety line to one side.

0:21:110:21:14

This could mean that Tim and Sara get pulled away with the line

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and have to waste precious air swimming against the current.

0:21:170:21:20

In that case, they might not make it all the way down

0:21:200:21:22

to the target 50 metres.

0:21:220:21:24

So here we are. The boats are in position.

0:21:240:21:27

Before I set you off, I've done a little bit of an experiment.

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-Have a look at this metal bottle.

-Yeah.

0:21:310:21:34

See if you can crush it.

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Oh, it's really strong, isn't it?

0:21:360:21:38

-Not really making any inroads, are you, Tim?

-No. None at all.

0:21:380:21:41

I sent an identical bottle down to the sort of depths

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that Sara's going dive to.

0:21:450:21:47

Dr Megan has placed cameras on the bottle

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to show what the pressure does at just 30 metres.

0:21:490:21:52

Oh, my word.

0:21:550:21:57

-And look what happened.

-Whoa!

0:22:000:22:03

That's the effect of the pressure down at depths, crushing in.

0:22:030:22:07

It's what would happen to your body if we sent you down.

0:22:070:22:10

The deeper you dive, the more your body gets

0:22:100:22:13

squashed by the pressure of water around you.

0:22:130:22:16

The pressure is so strong, it can burst your eardrums.

0:22:160:22:20

The deeper you go, the more your body gets squeezed, and soon your lungs

0:22:200:22:24

get squashed so they'll only be the size of oranges.

0:22:240:22:27

Blood and bodily fluids get pushed into your lungs

0:22:270:22:29

and they can start to bleed.

0:22:290:22:32

When you dive below ten metres, you will stop being able to float

0:22:320:22:35

and you'll be sucked down towards the bottom.

0:22:350:22:37

And if you try to come back up, the sudden change in water pressure

0:22:370:22:40

can make you pass out.

0:22:400:22:42

Then you'll run out of oxygen and die.

0:22:420:22:45

I'm afraid, Tim, I've got some bad news.

0:22:460:22:49

Because of that, the BBC safety authorities have decided

0:22:490:22:53

you just can't try this challenge.

0:22:530:22:55

Whoa, OK. I mean, Sara, it's really that dangerous?

0:22:550:22:59

With no training, absolutely.

0:22:590:23:00

There are many, many risks involved with freediving.

0:23:000:23:04

If you don't know what you're doing,

0:23:040:23:06

you should never, ever have a go on your own.

0:23:060:23:08

So I appreciate that possibly today is not your day.

0:23:080:23:12

But today might not be Sara's day, either.

0:23:140:23:16

Although she's dived twice as deep to over 100 metres,

0:23:160:23:19

setting her own personal record in the past,

0:23:190:23:22

the choppy sea conditions today are still a cause for concern.

0:23:220:23:25

It could cause her big problems in the dive.

0:23:250:23:28

OK, we've set the rope,

0:23:280:23:30

and we do have quite a bit of current today, actually.

0:23:300:23:33

So the rope is kind of at this angle, which isn't ideal.

0:23:330:23:36

It's also less than ten metres' visibility.

0:23:360:23:38

So these are both conditions that I'm really not used to diving in.

0:23:380:23:41

For Sara's dive, I'll be fitting her with this specialist dive computer.

0:23:410:23:45

It'll give me readouts of her heartrate

0:23:450:23:47

as she goes through the dive.

0:23:470:23:48

It'll be really interesting to see what story that tells.

0:23:480:23:51

Are you happy with that, guys?

0:23:510:23:53

Before each dive, Sara goes through a preparation routine.

0:23:550:23:58

She takes controlled breaths and relaxes her body, ready to begin

0:24:000:24:03

the attempt to make the incredible 50-metre dive in one breath.

0:24:030:24:07

Sara's done all her breathing exercises and warm-up,

0:24:090:24:12

she's ready to go. Good luck, Sara.

0:24:120:24:14

She's away!

0:24:180:24:19

For safety, Sara is tethered to the rope.

0:24:210:24:24

Without it, she might drift off course and get lost.

0:24:240:24:27

Amazing, she's like a massive big fish, isn't she? Beautiful,

0:24:270:24:30

stunning, willowing through the water with the big fins coming out

0:24:300:24:34

-behind her. It's amazing.

-She's like a beautiful silver mermaid, Tim.

0:24:340:24:38

As the air in her lungs is squashed, she becomes less buoyant.

0:24:390:24:43

If she passes out now, she'll just carry on sinking.

0:24:430:24:47

She's just gone past the point where she doesn't need to paddle any more,

0:24:470:24:51

because your body suddenly gets heavier and you get sucked down.

0:24:510:24:55

Sara is at the point now that the bottle crushed in the experiment.

0:24:550:24:59

From years of training, Sara can withstand the pressure,

0:24:590:25:01

being able to equalise her ears,

0:25:010:25:03

and her amazing diaphragm stretching to allow the shrinking of her lungs.

0:25:030:25:07

She just seems so very relaxed in the water. That's amazing, isn't it?

0:25:110:25:15

She uses a lot less oxygen so she needs a lot less air,

0:25:150:25:18

so she can keep going for longer.

0:25:180:25:20

With every metre she goes down, the pressure crushes her more.

0:25:200:25:24

and she has less and less oxygen left in her lungs.

0:25:240:25:27

So she's getting to the bottom now. She's nearly 50 metres down.

0:25:270:25:30

-It's incredible. 50 metres is a really long way.

-It's phenomenal.

0:25:300:25:35

She's reached the bottom. It's amazing!

0:25:350:25:38

50 metres down with just one breath of air -

0:25:380:25:41

and all under crushing pressure.

0:25:410:25:43

A normal person would be in agony as the water pressure

0:25:430:25:47

squeezed on their chest, and they would suffer burst eardrums.

0:25:470:25:50

The pressure on her body, the squeezing must be incredible.

0:25:520:25:55

Her heartrate's now down at 46,

0:25:550:25:57

that's less than half what it was at the surface.

0:25:570:25:59

But, unbelievably,

0:25:590:26:01

the most dangerous part of the test is still ahead of her.

0:26:010:26:04

Her body would have a huge amount of pressure on it,

0:26:060:26:08

squishing her lungs in, squishing in on her ears and her head.

0:26:080:26:12

She could start to get light-headed if she doesn't come up.

0:26:120:26:14

Only Sara's awesome abilities

0:26:140:26:17

and years of training allow her to make an attempt like this.

0:26:170:26:20

Don't ever try something like this yourselves.

0:26:200:26:23

Sara has been down for nearly two minutes.

0:26:240:26:27

So far, she is fighting the body's natural desire to breathe,

0:26:280:26:31

but there's still a long way to go.

0:26:310:26:34

The most dangerous part of this dive is the last ten metres.

0:26:370:26:41

This is usually the point that freedivers black out

0:26:410:26:44

from lack of oxygen. And it's happened to Sara herself before.

0:26:440:26:48

For that reason, it's essential that a safety freediver is waiting

0:26:480:26:52

to guide her up for the last stretch.

0:26:520:26:54

If she blacks out now, he'll need to save her.

0:26:540:26:57

Sara, that was truly one of the most magical things I've ever seen.

0:27:080:27:11

You are one of the most incredible people I've ever met.

0:27:110:27:14

It's just been a pleasure sharing this wonderful sport with you.

0:27:140:27:17

I came to the Emirates to find a real-life superhuman,

0:27:170:27:20

a person who could dive deeper and longer than any normal human.

0:27:200:27:25

I found one. Sara Campbell, you are superhuman.

0:27:250:27:30

Sara Campbell is one of the world's top freedivers,

0:27:330:27:36

with years of training and experience.

0:27:360:27:38

Do not attempt any of the activities shown in this programme.

0:27:380:27:42

You will be putting your life in danger.

0:27:420:27:44

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0:27:510:27:54

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