• 3 months ago
Michael.Mosley.Wonders.of.the.Human.Body.S01E02
Transcript
00:00One of Michael's greatest passions has always been to reveal the extraordinary secrets of
00:13how our bodies work.
00:18He spent several months with the production team, travelling far and wide for this brand
00:27new series on the human body.
00:32The family and I are delighted to introduce it to you.
00:37Michael even persuaded me to participate, tipping him upside down, as well as filling
00:46his ice bath, all in the name of science.
00:52And I'm sure he would have enjoyed the programme.
01:05We're heading off on an extraordinary journey around the human body.
01:10And if you give us a little chuckle.
01:15Have you ever wondered why we get creaky joints?
01:19Does your body hold the power to stop cancer from multiplying?
01:25How do you remember to breathe?
01:29I'll be tracking down answers to lots of burning questions.
01:33I feel quite a strong desire to urinate, but don't.
01:38From what exactly is in our farts?
01:41This device, which we colloquially refer to as the thunder funnel.
01:45That's great.
01:46To how long we take to digest our food.
01:48Are you wearing this every night?
01:49Absolutely.
01:50I'll show you how we can all live healthier, longer lives.
01:57This is one of the most impressive things I've seen for a very long time.
02:01And I put my body to the test to help you at home understand yours.
02:11Get ready to see yourself in a whole new light.
02:18This time, we go behind the scenes at Britain's biggest blood factory to find out why blood
02:29is such a wonder of the human body.
02:32There's about 26 trillion red cells in your body.
02:37At this factory, they work 24-7 to ensure that if you ever have to have a transfusion,
02:43you get the blood you need.
02:44I'll find out how we can reduce our blood pressure without needing stretchy exercise
02:49wear or joining an expensive gym.
02:52This is a real thigh burner.
02:55Plus a bodily function we all do as many as 15 times a day.
03:01But what is it about breaking wind that makes you feel you need to blame the dog?
03:08Wonders of the human body tackles the burning questions that you might have about your own
03:12body.
03:18I'm starting out by looking for answers to a silent killer, which is incredibly common
03:24but often missed.
03:26I'm talking about high blood pressure.
03:33Your heart is there to drive blood around your body.
03:36This powerful muscle pumps away and blood pressure is the force of the blood pushing
03:42against the walls of the vessels.
03:44Your blood pressure is a measure of the pressure on your arteries when your heart contracts
03:48and when it relaxes.
03:52That's why it's two numbers.
03:54The pressure is highest when your heart is contracting and lowest when it's relaxing.
04:01Everyone is different but a healthy blood pressure should be less than 120 over 80.
04:10More than half of Brits over 65 have unhealthy blood pressure.
04:19To illustrate what's going wrong I'm going to need a really big pump.
04:34Now imagine this hose over here is an artery and the engine over there is the heart.
04:42Now the heart is working to pump blood through this hose to the hungry organs of the body.
04:49Okay lads, keep going.
04:53Which is fine if your arteries are nice and supple.
04:58The trouble is that as we get older these arteries tend to become stiffer and narrower
05:05and that means that you need even more pressure.
05:10So your heart has to pump harder.
05:13All that extra pressure puts strain on the heart and also damages the lining of the arteries.
05:22Even if you feel fine it is important that you get your blood pressure checked regularly,
05:27especially if you're over 50.
05:31High blood pressure is known as the silent killer because it often comes without symptoms
05:35and unless you've got a machine like this you're not going to know you have it
05:39until perhaps you have a heart attack or a stroke.
05:42I feel particularly strongly about this because I have several close friends
05:46who've died as a result of untreated high blood pressure.
05:53Luckily, that's simple exercises you can do at home which can reduce blood pressure.
05:58Okay, so this is the plank.
06:02The idea is you go up in your elbows, keep your body straight and hold this for as long as you can,
06:07ideally for up to two minutes, which I can assure you is a long time if you're doing the plank.
06:13Isometric exercises, where you tighten your muscles but don't actually move them
06:18like the plank or the wall sit, can help reduce blood pressure in the comfort of your own home.
06:24So this is the wall sit, you put your legs out about two feet and this is a real thigh burner.
06:31Well, maybe comfort was the wrong word.
06:34The idea is you try and hold it for about 20 to 30 seconds,
06:38you have a breather and you go and do it again another couple of times.
06:42Right.
06:44Now, this is a surprising one and it's particularly suitable if you can't do more conventional exercise.
06:51Now, what you have to do is you have to grip this thing and the idea is you squeeze it
06:56and then you hold it for a couple of minutes and you do it again a couple more times
07:00and you try and do this about three times a week.
07:03You can get hold of these grip strengtheners pretty easily online.
07:08So how exactly do these sorts of exercises help reduce blood pressure?
07:15Inside your muscles, you have a network of blood vessels.
07:22When you hold an exercise pose, the muscles squeeze your blood vessels.
07:28Then when you stop squeezing, the sudden rush of blood expands your vessels again.
07:35Repeating this on a regular basis makes your blood vessels more supple
07:39and because they are now more supple, this helps lower your blood pressure.
07:45It really is impressive the way that these relatively simple exercises can bring your blood pressure down
07:50and it also shows how remarkable your body is that it can self-repair if you give it the chance.
07:58Don't panic if you get an occasional high reading.
08:00Many things affect blood pressure such as poor sleep or stress
08:04and as well as helping lower blood pressure, daily exercise is also very good for your joints.
08:11Every hop, skip or jump I have made or will ever make is thanks to my hips.
08:19I want to find out more about these remarkable bones.
08:22Our hips start out strong and mobile
08:25but the sad fact is that one in ten of us will eventually need hip replacement surgery.
08:30So, can we reverse our hip destiny?
08:40To keep working efficiently, our hip joints rely on the most slippery natural substance ever discovered.
08:47Ha ha!
08:50Not ice, but cartilage.
08:54Cartilage is amazingly flexible and also acts as a shock absorber.
08:58It doesn't have a nerve supply so it's ideal for wherever two bones meet,
09:03preventing them rubbing against each other.
09:07This ice is very slippery which is why I'm walking with caution
09:12but cartilage is actually five times more slippery than ice.
09:17Super slippy cartilage plus a watery lubricant made by your blood helps your joints move with ease.
09:26But we certainly notice when it goes wrong.
09:29In middle sex, there's someone who knows all too well the agony that hip problems can bring.
09:35Just constant pain throughout the day.
09:39Getting in and out of the car is difficult.
09:41Just doing housework, gardening can be extremely difficult.
09:4743-year-old Claire Haywood has been admitted for an urgent hip replacement.
09:53She has osteoarthritis, a condition where the cartilage in her hip joint has largely disintegrated,
09:59leaving the bones to rub against each other and wear away.
10:04A consultant has just told me this morning it looks like my left hip is about to collapse
10:08because the bone has worn away that much.
10:12It's osteoarthritis.
10:15I've had trouble throughout my whole life with my hips.
10:19Today I'm feeling a little bit overwhelmed.
10:21Feeling quite emotional because I'm looking forward to actually being pain free
10:26and I worry about my kids.
10:27I just worry, you know, hopefully I'm going to be OK, there's no complications
10:31and I can get home within the next couple of days.
10:35Osteoarthritis can be inherited or the result of injury or overuse.
10:40Once the cartilage has disintegrated, your best bet is a new hip.
10:44And a pair of eight gloves for me, please.
10:48At the Royal National Orthopaedic Hospital in Stanmore,
10:51they're hoping a new kind of hip surgery, pioneered here, will help change Clare's life.
10:59I am looking forward to this.
11:00It's been a long time since I've seen an orthopaedic operation
11:05and I imagine it has changed a great deal in that time.
11:10Just pull it down up front.
11:13Coming up, an extraordinary ability most of us have no idea we possess.
11:19I get to the bottom of what's really in our farts.
11:22Now, farting may not sound like one of the wonders of the human body,
11:26but it is a fascinating subject and one I'm going to explore further
11:30with the help of this portable gas monitor.
11:34And blood, what exactly is in it?
11:37So, there you go, a lovely drop of fresh blood.
11:49I'm not normally a heavy drinker, but for the sake of this programme,
11:53I thought I would pop into a local pub.
11:57Poppin' in.
11:59Brilliant. Could I get a...
12:03Poppin' in.
12:05Brilliant. Could I get a pint of your best, please?
12:10Lovely.
12:13And could I get another pint, please?
12:16Fantastic. Thank you.
12:18And could I get another pint, please?
12:20Could I get another pint, please? And I would like one more pint, please.
12:25Have you ever wondered how much blood there is in the human body?
12:29Well, it comes to around five litres, which is about nine pints.
12:37Many of us give blood just under a pint at a time.
12:41But what's in blood makes it such a precious and life-saving liquid.
12:46We're heading to Bristol
12:48and one of the biggest blood-processing plants in the world.
12:53GUNSHOT
13:01Regular blood donor Mishak Snape has already given an impressive 30 pints.
13:09My older sister was always donating blood,
13:11so from seeing her doing it all the time,
13:13she encouraged me to start doing it and from then I haven't looked back.
13:17And today he's getting inside the factory.
13:20To find out first-hand what happens to the blood we donate.
13:23It's almost like you're in a chocolate factory,
13:26obviously there's nothing you can eat.
13:28It's just amazing.
13:30Blood doctor Lee's escort is leading his tour.
13:34Amazing, amazing facility this is.
13:37Yeah, so all the blood from Midlands and the south-west comes into this unit.
13:42So your donation will come into this unit to be processed.
13:46Once the precious donated blood arrives,
13:49it is carefully separated out into different component parts by machines.
13:55As you might expect, almost half of your blood is made up of red blood cells,
14:00essential for delivering oxygen everywhere our bodies need it.
14:04The rest is plasma, a fluid that is crucial for health and longevity.
14:09As well as carrying white cells that fight infection and disease,
14:13your plasma transports platelets that are essential for blood clotting.
14:19Plasma is great because we can make it into a product
14:23we give to people who are bleeding.
14:25It can help stop them bleeding.
14:27It also contains antibodies and that can be used for people
14:31who don't have a good immune system
14:34and can help them fight infections.
14:37Oh, OK.
14:39This place is impressive, but so is the fact
14:42that your body can churn out new blood cells at an extraordinary rate.
14:48And you're making between two and three million red cells a second.
14:53That's why you can donate blood and your body kind of...
14:57Replenishes it. Replenishes it and makes more.
15:00Every precious donation helps places like this one do their life-saving work.
15:05All those different parts means that we can save up to three lives
15:08with each donation.
15:10Oh, OK.
15:12I want to give blood until I can't no more.
15:14I'm just going to carry on giving blood.
15:16Hopefully encourage others to give blood.
15:18There's no other pint quite like it.
15:21Cheers.
15:28Back in Stanmore, 43-year-old Claire is hoping to have a baby.
15:3343-year-old Claire is hoping to have her life transformed later today.
15:39Leading the surgical team at the Royal National Orthopaedic Hospital
15:42is Professor Alastair Hart.
15:45So can you tell me about Claire?
15:47She is a young lady,
15:49considering the average age of patients that we give hip replacement to.
15:54In the UK, the average age is about 67.
15:57Alastair shows me what can happen when hip joints like Claire's
16:01lose their protective coating of cartilage.
16:06This is what can go wrong, slightly more unusual.
16:09So in this hip...
16:15..the cartilage has worn off and you've got bone rubbing against bone.
16:19Right. That's what's causing squeaking.
16:23Ooh. Wow. Was she in a lot of pain?
16:26Agony, yeah.
16:29To save her from further pain and disability,
16:32Alastair will remove the damaged head of Claire's thigh bone
16:36and fit an artificial implant.
16:39It's proved extremely hard to mimic a human hip
16:42because it's such an extraordinary bit of biological engineering.
16:47So, second patient, Claire, are you happy?
16:51Good. Thanks a lot.
16:54Most artificial hips fail after 25 years.
16:57Often because it's so very hard to achieve a design and fit that's precise.
17:03That one needs to come up a little bit.
17:07Amongst other things, Alastair and the team use a plastic 3D printed model
17:11which helps him decide exactly where to cut Claire's bone.
17:16Positioning her new hip implant precisely should ensure it lasts longer.
17:22And we're now going into the hip joint itself, into the capsule.
17:27So, step one will be the removal of the head of the femur, will it?
17:30Yes.
17:31Alastair shows me the plastic model he's made of Claire's existing thigh bone.
17:36These are unique to this lady. OK.
17:38That's the top of her thigh bone, femur. OK.
17:41It's really knackered, isn't it? Yes. It's very distorted.
17:46These are unique to Claire.
17:49These are unique.
17:53And this piece fits very nicely.
17:57OK.
17:58Showing us exactly where to make the cut. OK.
18:00And the previous method generally involves an orthopaedic surgeon
18:05using their finger. Yes.
18:07And very approximate. And you've got to be right within degrees, this one.
18:11Wow.
18:13These can come out.
18:14What those 3D models allow him to do is to align the bits up perfectly
18:19and that means that there's much less chance that this hip will fail.
18:26So, this is the moment of truth. Right. Yep.
18:28So, will this guide... That's the 3D model.
18:31..actually fit onto the patient's... Yep. OK.
18:36If this doesn't work and the artificial hip fails,
18:39Claire will be in terrible pain all over again.
18:44OK.
18:50The next stopping point on our journey around our bodies
18:53is truly eye-opening.
18:56The human eye is another wonderful example of biological engineering.
19:00Sight is so important to us
19:02that more than half the surface of our brains, the cortex,
19:06is dedicated to processing visual information.
19:10But even if we are without vision,
19:13we can still draw on a hidden superpower.
19:20Anybody who loses vision in the way that I did,
19:23very suddenly and very quickly, it's incredibly difficult.
19:27Jane Hyde Dryden lost her sight in her 40s
19:30after she developed a condition called glaucoma,
19:33which caused damage to her optic nerves.
19:36I remember sitting in my living room,
19:39not really being able to move around my house properly,
19:42I had to stand up from the chair and move to the door,
19:45and I just felt very, very alone in this dark world.
19:56Jane is now totally blind.
19:59But her world has been opened up by a startling new skill,
20:03something we usually associate with bats or dolphins.
20:07Echolocation.
20:13Echolocation has absolutely transformed my life.
20:17It basically involves the tongue hitting the roof of the mouth.
20:25The sound travels to the object and back to my ears.
20:35If an echo comes back quickly, the object is close.
20:39If it takes longer, the object is further away.
20:44And then what happens is something magical in the brain happens
20:48where the sound is transferred into an image.
20:52I use echolocation every single day.
20:57The idea you can be trained to see using sound is extraordinary,
21:01but Jane's living proof.
21:04I sense things throughout my entire body when I'm walking round.
21:08Which sounds a bit odd and a bit weird.
21:12But I can determine if something is hard or if it's soft,
21:17how high it is. I can see different textures.
21:22I tend to take real note of my environment.
21:31Jane was taught how to echolocate by Dr Laura Tala at Durham University.
21:38Amazingly, apparently anyone can do it, if they learn how.
21:45So we have an object in front of you. It's a plank shape.
21:49So it can be vertically or it could be horizontal.
21:52So your task is to echolocate it and then tell us which orientation it is.
21:57Alright.
21:59CLICKING
22:07That's right, horizontal. Yeah.
22:10After five years of training, Jane now gets it right about nine out of ten times.
22:19When I echolocate with something, am I using a similar part of the brain
22:24to someone who's looking at something?
22:26So that seems to be... Yeah.
22:28That is just so cool, isn't it? Yeah.
22:31Laura has shown that as well as the visually impaired,
22:34sighted people can also learn to echolocate if they practise hard enough.
22:42What was amazing also that the people who are blind got better,
22:46but also the people who are sighted.
22:48Everyone got better.
22:50I think it's just so cool that everyone has the ability to learn this technique.
22:56CLICKING
23:04And actually, everyone does echolocation naturally, I would suspect.
23:08So there will have been times, I'm sure,
23:11when people have gone to the toilet in the middle of the night
23:14and they have stopped because they know they're going to walk into the doorframe.
23:20That is your inbuilt passive echolocation, working overtime.
23:27For me, I'm really proud to be able to just move with freedom.
23:38For all of us, sighted or not,
23:40the world can, at times, feel like it's designed to stress us out.
23:45And long-term chronic stress has been blamed for a host of serious conditions,
23:50from heart disease to depression and even Alzheimer's.
23:54But being stressed is not always a bad thing.
24:01To help explore our body's response to stress
24:04and find out what we can do about it...
24:07I felt a little frisson of fear there.
24:10..I put myself in a very unnatural situation.
24:14I'm halfway up a crag.
24:17There's quite a long way down, but there's an awful long way up,
24:20and this is the hard bit.
24:25The classical fight-or-flight response is of such interest to us
24:30because from an evolutionary perspective,
24:32it's perhaps what allows us as a species to have survived,
24:36but we also experience it every day.
24:38You go into an interview or an exam or you have stress at work.
24:43It's the same response. It's a stress response.
24:45Coming up, I find out what stress is and how to overcome it
24:50if I can summon up enough courage to keep climbing.
24:54I talk about a cliffhanger.
24:57Plus, I explore the extraordinary science
25:00behind how we get around on two feet.
25:03Woo-hoo!
25:05It is incredibly windy in here.
25:08That is appropriate because I'm about to introduce you
25:12to one of the wonders of the human body that we don't often talk about.
25:16Did you know that women may fart more than men?
25:20Thank you very much. Over and done. You won.
25:22That's the head of her femur.
25:24And will a new approach to hip-replacement surgery
25:27give Claire her life back?
25:36We're in Snowdonia, where I'm on a mission to learn more
25:40about what stress does to our bodies.
25:42To do that, I'm putting myself through a very stressful experience,
25:46almost 100 metres up.
25:49Sorry, that's my hand.
25:5330 minutes earlier, I was rigged with a heart rate monitor
25:56by Jamie MacDonald, who is Professor of Sport and Exercise Science
26:00at Bangor University.
26:02What it allows us to do is just get a visual picture
26:06of what's happening to you as you respond to this fight-or-flight response.
26:10OK.
26:11I'm expecting the monitor will show I'm way outside my comfort zone.
26:15Unlike Jamie's colleague, Professor Tim Woodman,
26:18who's an experienced climber.
26:20There you go. I think he's doing very well.
26:22He's obviously a little bit anxious.
26:25Interesting. I'm definitely feeling uncomfortable now.
26:32So the green line here is Michael's heart rate response,
26:36and the orange line is Tim, who's climbing right next to him.
26:40That really does look quite vertical, doesn't it?
26:43It's starting to get a bit more steep, isn't it?
26:46What's interesting here is that they're doing the same amount of physical work,
26:50yet Michael's response is much greater.
26:56I do exercise regularly, but the amount my heart is facing
27:00is a clear sign of my stress response in action.
27:09OK. Blimey.
27:12Well done.
27:15So now Michael's overcome that initial anxiety.
27:21He needs to continue to be ready for activity.
27:25There's this amazing hormone called cortisol,
27:28and cortisol's known as the stress hormone.
27:35So the cortisol will keep his heart rate high,
27:37it will trigger his blood flow to different parts of the body,
27:40the muscles, the brain, and we're going to monitor that later
27:43when we measure the cortisol in his saliva.
27:46I've got my cortisol swab here, and you can see my mouth.
27:49Can you try me?
27:50Sorry, you have two minutes.
27:54OK, that's it for that.
27:55OK.
27:57OK, let's see what the result of that is.
28:00I'd be astonished if I'm not a bit stressed.
28:04Most of us have heard of the stress hormone cortisol.
28:09But how exactly does it work?
28:13When you're stressed, your brain sends a signal to glands near your kidneys,
28:17telling them to release cortisol into your bloodstream.
28:21That's normal.
28:22But if levels rise and stay high, that can be bad news.
28:27Too much exposure to cortisol can disrupt the body's normal processes.
28:33And that, in turn, can increase your risk of serious health problems,
28:37such as high blood pressure and diabetes.
28:42Coming up. Oh, a bit stiff.
28:44So I am feeling sort of panic.
28:51But I overcome my fear and make it to the top,
28:55and the view was well worth it.
29:03I'm no mountain goat, that's for sure.
29:06With my ordeal finally over, it's time to regroup with Jamie at the bottom.
29:11Hi there. Oh, blimey, that was hard.
29:15The test reveals that my cortisol was a whopping three times the expected level.
29:20And the effects can hang around for a few hours,
29:22so I'll probably have elevated blood pressure even after my heart rate comes down.
29:27But the odd thing is, I also quite enjoyed it.
29:30I have to say, from a just purely personal point of view,
29:33feeling halfway up, never, ever, ever want to do this again.
29:37But on top, I was thinking, actually, yeah, I could do this again.
29:44A short, stressful challenge like mountain climbing can give us a feel-good buzz.
29:50But chronic stress is really bad for us.
29:53Fortunately, there are some easy things you can do to manage chronic stress
29:57and help improve your health and longevity.
30:00Having a good laugh will reduce cortisol levels.
30:05Getting active and also practising deep breathing
30:08is especially good for calming your nervous system.
30:12And a dose of fresh air, preferably somewhere green, is always good for stress.
30:19In Stanmore, mum-of-two Claire has been admitted
30:22for what she hopes will be life-changing surgery.
30:27Leading orthopaedic surgeon Alistair Hart is at the critical stage of the operation.
30:33So this is the moment of truth? Right, yep.
30:36Earlier, he made a plastic model designed to test how well the real hip implant will fit
30:41when he puts it in place.
30:43So that's it. It's very like Lego.
30:48And that fits very nicely to me.
30:50Yeah, it looks beautiful.
30:52That's very solid.
30:55The plastic template can now be put aside.
30:58It has done its job, showing Alistair exactly where he needs to cut through bone.
31:05So that shows you exactly where you've got to cut through bone.
31:10So that shows you exactly where you've got to cut.
31:13Make the cuts.
31:15Here we go.
31:20So you just cut through the bone?
31:22She's got absolutely no cartilage here at all.
31:25So this should be nice and soft.
31:29And it's rock hard.
31:31And she's been walking on that and it's a very painful joint.
31:35Claire's new, custom-built artificial hip is now ready to be fitted.
31:40So that's a short, right?
31:46And just over an hour after starting, Claire's new hip is in place.
31:50So that's her new hip articulation.
31:53Brilliant. And within a day or two, she's going to be up and about?
31:57She'll be walking tomorrow morning, yeah.
31:59Maybe later this evening, if she's keen.
32:02Right. I think the operation is done.
32:05Only time will tell if Claire's new hip will be a success.
32:09Good day's work? Yes.
32:16If you experience discomfort in your hips or your lower back,
32:20it could be down to how you walk.
32:24No-one really knows why humans first started walking upright.
32:28No-one really knows why humans first started walking upright.
32:31But with an erect posture came back problems.
32:36Here at the Edinburgh Centre for Robotics,
32:38they're studying exactly how we manage to get around on two feet,
32:42with the long-term goal of helping those who can't.
32:46And they're doing this with the help of some very unusual lab assistants.
32:51Ooh, very good.
32:54It reminds me of teaching my children to walk,
32:57where basically you have to grab them just as the bat keel over.
33:02Whoa! There we go.
33:05Professor Sethu Vijayakumar is leading the team, and today I'm his guinea pig.
33:11We're going to try running some walking tests on you.
33:15We don't normally think that much about how we walk, we just do it.
33:19So I'll be intrigued to see what the researchers make of my walking.
33:23OK, what do you think? You're looking good.
33:25Looking good. Thank you very much. OK.
33:28On the treadmill, cameras track sensors which are attached to my body
33:32to record my exact movements.
33:36We actually can see you in real time on the screen,
33:40the skeleton of you walking.
33:43When humans walk, we tend to walk by falling forward.
33:47Yeah. OK.
33:50If you look carefully, you can see I'm always off balance,
33:54slightly tipping forward.
33:57But what's amazing is my body constantly senses the ground beneath me,
34:01allowing me to respond to changing terrain without needing to think about it.
34:06I did not expect it to do that.
34:08So how does your body manage to react so well to surprise?
34:13Now, I was able to correct myself almost immediately on that.
34:17You get an unexpected event, like a push,
34:20then your automatic part kicks in,
34:24where it prevents you from falling over.
34:29The secret to this lies in something called your reflex arc.
34:33When your legs start to stumble, nerve signals travel to your spinal cord.
34:37Messages then go straight back to your legs,
34:40telling them how to correct your balance.
34:43For the sake of speed, your reflexes actually bypass your brain.
34:50Walking, of course, is very good for us.
34:52If everyone did at least 15 minutes a day,
34:55as many as one in ten premature deaths could be prevented.
35:05Our bodies have evolved to walk upright,
35:08helped by large muscles in the bum,
35:11the aptly named gluteus maximus,
35:13by our Achilles tendons,
35:16and even by the arches in our feet.
35:21Of course, cardio workouts that you can do sitting down
35:25will also provide health benefits.
35:30Whoa! Weird.
35:32Sethu also wants to use the research being done here
35:35to help people regain mobility.
35:38This is a small step for me, but a giant step for mankind.
35:42Hey, I love the noise, I have to say.
35:46This is an exoskeleton.
35:49A wearable robot.
35:51So, just gently...
35:54That is very weird.
35:56There's part of me which is quite confident that I can probably...
36:00I can't dance, but I can absolutely move.
36:03Turn, yeah.
36:08The exoskeleton can support itself,
36:10and let's say you were somebody with a disability
36:14and you didn't have the force to actually move your legs,
36:17then this exoskeleton could kick in at that point and assist you
36:21such that you feel like you're walking normally.
36:23For many people, that would be a big thing.
36:25Absolutely.
36:27OK, I'm feeling confident. Yeah.
36:31For people who've had an injury, a stroke,
36:34or a condition like Parkinson's,
36:36exoskeletons like this one could one day support them
36:40as they learn to walk again.
36:42How long do you think before people are going to start
36:45wearing these in a more routine way?
36:47I think it's going to be at least five to ten years.
36:50That's a long time to wait,
36:52but in the meantime, I can promise you they're a lot of fun.
36:56No, it's cool.
36:58So now I know what it feels like to be a cyborg.
37:04Time to move on from something incredibly high-tech
37:07to something that's far more down-to-earth.
37:11It is incredibly windy in here, and that is appropriate
37:15because I'm about to introduce you
37:18to one of the wonders of the human body
37:20that we don't often talk about.
37:24And that is breaking wind.
37:28So what is it that happens when we fart?
37:32And what is in those farts?
37:35Whoo!
37:41At least this is an experiment that I can do at home.
37:45I'm trying to produce a fart to see what's in it.
37:49While we wait, here are some fabulous farty facts.
37:54So, on average, we produce up to a litre of gas a day.
38:01And then, of course, we release it.
38:04We know these numbers because scientists have studied
38:08this serious subject by putting tubes up people's rectums.
38:18Studies have also shown that the average person farts
38:21up to 15 times a day, which, over a year, really adds up.
38:28Now, this is about 300 litres of gas,
38:31which is roughly the amount you produce every year.
38:35Chances are you or someone uncomfortably close to you
38:39is likely to break wind at least once before the end of this programme.
38:48Coming up, has Claire's pioneering hip surgery been a success
38:53and will she soon be pain-free for the first time in years?
38:57I reveal the different gases that make up your farts.
39:01You have some methane, so you're one of the lucky ones that has some methane.
39:05And just how flammable are farts?
39:08I urge you, do not try this at home.
39:24Our journey round the human body has taken us from the top to the bottom.
39:31I've come to Loughborough University to meet Professor Jim Reynolds.
39:35Jim has kindly offered to use his considerable scientific expertise
39:40to capture and test my farts.
39:44Hi, Jim. Ah, morning, Michael.
39:46Now, I gather you've been putting something together
39:49to help collect and analyse my farts, yes?
39:52That's correct, Michael.
39:54So this device, which we colloquially refer to as the thunder funnel...
39:57That's great. OK.
39:59Yeah, you might not want to sniff that.
40:02So this is a small pump.
40:04This will extract the gas and it will measure how much gas is released.
40:07Have you done this yourself? No comment.
40:10OK, so I'm assuming what happens is you just kind of lift that end, would you?
40:15That's correct. Place it there.
40:17We switch the pump on and then open the valve.
40:21And there we go. Brilliant.
40:23A fart in a bag.
40:25With the thunder funnel in place, it's now just a waiting game.
40:36There she blows.
40:38Woo-hoo! Heads up!
40:40Now that my wind's been captured, the team will analyse exactly what is in it,
40:45which, for me at least, is quite exciting.
40:48Chemist Michaela Dawkins will do the analysis.
40:51I have an offering for you. Thank you very much. That's quite a lot.
40:54So what are you expecting to find?
40:56So I'm going to find out what's in your farts.
40:59We're going to use this machine which is called a gas chromatographer.
41:02It separates out the gases and tells me what's in your fart, basically.
41:06Results time now.
41:10So let's bring up here.
41:12So this is you. So this is me.
41:15So first of all, most of it, as you can see, is air.
41:18So we have quite a lot of nitrogen and also carbon dioxide,
41:22which we find in the air around us.
41:26Most of the gas we release through our bottoms is just air we swallowed earlier.
41:31But it's not all hot air.
41:34Around 100 trillion bacteria live in your intestine.
41:38They help to break down food and release gas while they do it.
41:44The gut bacteria are obviously doing something.
41:47Yes, which is why we have the hydrogen coming through,
41:49which we find in everybody's farts.
41:51The thing which produces a lot of the smell, which we are incredibly sensitive to,
41:55is hydrogen sulfide.
41:57And where would you normally encounter it in the real world?
41:59So rotten food.
42:01Ah, OK. So really what it's measuring is rot, decay,
42:05something which is dangerous, and that's why it's so important to us.
42:08We can test for it. So we can use something called lead acetate paper
42:12and squeeze your gases over it.
42:15It should go brown, a browny-black colour, if there is enough in there yet.
42:21So the moment of truth. Are my farts smelly?
42:27Not at all brown, so good news.
42:29Not at all brown. So it's instant. Whoa! Hey!
42:32I may be producing farts, but they're not smelly.
42:35Have you analysed yours?
42:37No, not yet. Not yet. Brilliant.
42:42So there you have it.
42:44Many of the gases coming out of your rear end
42:47come from air you've swallowed earlier.
42:52Your gut bacteria make hydrogen and pongy hydrogen sulfide.
42:57But for most people, it's there in such tiny quantities,
43:00it barely registers.
43:03Despite the fact, your nose is super sharp
43:06at picking up every last drop of it.
43:09And there's another gas that some of us produce.
43:12Methane.
43:14Methane.
43:20I've just captured some methane gas inside these soapy bubbles.
43:26Let's see what happens when I light it.
43:36Whoa, that was magical.
43:38Now, as you can see, methane is incredibly flammable.
43:41It is a gas produced in your gut,
43:43and not all of us do so.
43:45In fact, only around one in four people produce methane.
43:48And obviously some people on the Internet
43:50are busy trying to light their farts.
43:52I would strongly recommend you don't do that.
43:59Whether or not you produce methane is down to your genes,
44:02your diet and your own individual mix of gut bacteria.
44:07When I first started looking into the subject of farts,
44:10I had no idea it was going to be quite as interesting as it is.
44:13But on the whole, the fact that we fart,
44:16well, that is just entirely human and nothing to be ashamed about.
44:29Remember Claire, who we followed having a pioneering hip replacement?
44:33Here she is ten weeks later.
44:37There's no pain.
44:39I used to get pain doing this machine, but now it feels great.
44:44Here's hoping that the cutting-edge surgical techniques we saw earlier
44:48will keep her, and others like her,
44:50pain-free and mobile for decades to come.
44:54The human body is full of surprises,
44:56and what's exciting is there is so much more to learn.
45:03Next time, how do you remember to breathe?
45:11Respiratory diseases are one of the main causes of death in the UK.
45:17We follow the extraordinary story of Clifford,
45:19who is undergoing pioneering lung surgery.
45:24I don't know what to expect.
45:27Breathe! One down, a billion to go.
45:30How exactly does your body react to invading viruses, like the flu?
45:35You're a nice drop now.
45:40And I reveal three things you can do
45:42to keep your brain in peak condition as you age.
45:47Whoa!