0:00:09 > 0:00:11# Super Human Challenge
0:00:13 > 0:00:16# S-U-P-E-R. #
0:00:23 > 0:00:24Running is fun...
0:00:25 > 0:00:27..and a great way to keep fit.
0:00:27 > 0:00:29But, sooner or later...
0:00:32 > 0:00:35..we all have to stop.
0:00:35 > 0:00:38Imagine a man who could run for ever.
0:00:38 > 0:00:42He would be a real life superhero.
0:00:42 > 0:00:47A superhero like Captain America, with amazing fitness, stamina
0:00:47 > 0:00:50and endurance, who can run for ever.
0:00:50 > 0:00:53And I've heard of a real man with unbelievable stamina.
0:00:53 > 0:00:55A man who is so strong,
0:00:55 > 0:00:59he can run and run and run without ever getting tired.
0:01:03 > 0:01:06When Dean Karnazes was 30 years old,
0:01:06 > 0:01:10he discovered he could run without ever getting tired.
0:01:10 > 0:01:13Known as Ultramarathon Man, for the last 20 years
0:01:13 > 0:01:16he has pushed his body to unimaginable limits.
0:01:16 > 0:01:20He runs in extreme temperatures without breaking a sweat and,
0:01:20 > 0:01:24amazingly, he has run for 350 miles,
0:01:24 > 0:01:26day and night, without stopping.
0:01:27 > 0:01:31Is Dean Karnazes a real life Captain America?
0:01:33 > 0:01:35Tim has travelled all the way to
0:01:35 > 0:01:38California in the USA to find out.
0:01:38 > 0:01:40And this is him - the man himself!
0:01:40 > 0:01:43Dean, thanks so much for meeting me, it's a real pleasure.
0:01:43 > 0:01:47- Likewise.- How did you discover you had this incredible stamina?
0:01:47 > 0:01:49One night I walked out at 11 o'clock
0:01:49 > 0:01:52at night, and started running,
0:01:52 > 0:01:54and ran straight through the night
0:01:54 > 0:01:56and ran 30 miles in seven hours.
0:01:56 > 0:01:58I thought, "How did I just do that?"
0:01:58 > 0:01:59That was the night, yeah.
0:01:59 > 0:02:01So can you run for ever?
0:02:01 > 0:02:03I can run for a long, long time.
0:02:03 > 0:02:05I don't know about for ever, but a long, long time.
0:02:05 > 0:02:08OK, we would like to measure your superhuman abilities
0:02:08 > 0:02:10by putting you through three different tests,
0:02:10 > 0:02:13and measuring you against a very average guy - me.
0:02:13 > 0:02:15Would you be up for that?
0:02:15 > 0:02:17Let's do it, yeah, I'm in. Let's go.
0:02:18 > 0:02:20This is Dr Megan John.
0:02:20 > 0:02:23She's an expedition doctor and has kept people alive while they've
0:02:23 > 0:02:28attempted some of the most dangerous activities you could imagine.
0:02:28 > 0:02:31She's created three Super Tests to try to find out
0:02:31 > 0:02:35if Dean Karnazes really is a Super Human.
0:02:36 > 0:02:38For my Super Test One I've brought the two of you to
0:02:38 > 0:02:41the University of California's Elite Performance Lab.
0:02:41 > 0:02:44I'm going to be seeing how your heart and lungs
0:02:44 > 0:02:46cope with really tough exercise.
0:02:46 > 0:02:49I hope you both like cycling, cos today you're going to be
0:02:49 > 0:02:52pedalling till your legs turn to jelly.
0:02:52 > 0:02:53Cycling? I thought you were a runner?
0:02:53 > 0:02:55- I'm a runner. Are you a cyclist?- No.
0:02:55 > 0:02:57Who said anything about cycling?
0:03:00 > 0:03:02So, the two of you are going to take it in turns
0:03:02 > 0:03:04to pedal on this bicycle.
0:03:04 > 0:03:08Might sound easy, but it's been pre-programmed to get harder
0:03:08 > 0:03:09and harder and harder for you.
0:03:09 > 0:03:12I'm going to be measuring the amount of oxygen your muscles
0:03:12 > 0:03:14are using for the exercise.
0:03:14 > 0:03:16At some point, your body's going to reach its limit
0:03:16 > 0:03:18and then it'll be game over for you.
0:03:18 > 0:03:20That's what we call your VO2 max,
0:03:20 > 0:03:22ie, the maximum amount of oxygen
0:03:22 > 0:03:25your body can use during exercise.
0:03:25 > 0:03:27Sounds fun to me - let's try it.
0:03:27 > 0:03:29Come on, boys, let's get on with it.
0:03:30 > 0:03:34The VO2 max scores differ depending on your age and Megan wants to
0:03:34 > 0:03:39see how Tim and Dean compare to the average scores for their age groups.
0:03:39 > 0:03:42Tim is 36 years old and the average
0:03:42 > 0:03:45VO2 max for a man of his age is about 45.
0:03:45 > 0:03:50Dean is 50 years old and the average for his age is about 32.
0:03:50 > 0:03:52During the test, Megan will also be
0:03:52 > 0:03:54keeping a check on their heart rates,
0:03:54 > 0:03:56to make sure they're not in danger.
0:03:57 > 0:04:00Now, this is going to get really, really tough, guys.
0:04:00 > 0:04:03It's going to get tough because when you start exercising
0:04:03 > 0:04:06you breathe harder and your heart beats faster.
0:04:06 > 0:04:09You get really hot and you begin to sweat.
0:04:09 > 0:04:12Your body struggles to get enough oxygen,
0:04:12 > 0:04:15so soon your muscles will start to ache.
0:04:15 > 0:04:17If your heart beats too fast, you could get dizzy or faint
0:04:17 > 0:04:19and eventually collapse.
0:04:19 > 0:04:21In really extreme cases,
0:04:21 > 0:04:23you could have a heart attack
0:04:23 > 0:04:24and die.
0:04:24 > 0:04:27Tim Fitzhigham, part man, part machine, ready to be tested
0:04:27 > 0:04:29for certainly one minute,
0:04:29 > 0:04:31hopefully a little bit longer.
0:04:31 > 0:04:33Yeah, well, fingers crossed, Tim.
0:04:33 > 0:04:35Now, the oxygen we use comes from the air.
0:04:35 > 0:04:37Air is made up of many different gasses,
0:04:37 > 0:04:40so Tim and Dean will need to breathe through a special tube, so that the
0:04:40 > 0:04:45equipment can measure exactly how much oxygen their bodies use.
0:04:45 > 0:04:48- MAN:- So you won't be able to talk to us during the...
0:04:48 > 0:04:50You've been waiting for this, haven't you?
0:04:50 > 0:04:52Tim is taking the test first,
0:04:52 > 0:04:56with Dean climbing on for his test straight afterwards.
0:04:56 > 0:04:58- MAN:- OK, you can go ahead and start pedalling.
0:05:00 > 0:05:02Right, we are starting the test now.
0:05:05 > 0:05:09Before the test, Tim's heart rate was 62 beats per minute
0:05:09 > 0:05:12and his VO2 was ten.
0:05:12 > 0:05:16As he begins to exercise, his heart starts beating faster.
0:05:16 > 0:05:19So Tim's heart rate's already up at about 120 and we know
0:05:19 > 0:05:21his resting level's about 60,
0:05:21 > 0:05:23so he's about double that already.
0:05:23 > 0:05:26You're doing really well, Tim.
0:05:29 > 0:05:30- MAN:- Good to go?
0:05:30 > 0:05:32OK.
0:05:35 > 0:05:39Before the start of Dean's test, his VO2 was much lower than Tim's,
0:05:39 > 0:05:42at only six, and his heart rate was lower too,
0:05:42 > 0:05:44at only 40 beats per minute.
0:05:46 > 0:05:49With exercise, his heart starts to beat faster, but it's still
0:05:49 > 0:05:53only about the same as Tim's before he'd even started exercising.
0:05:55 > 0:05:57Dean's heart rate's going about 66,
0:05:57 > 0:05:59so he's really nice and relaxed.
0:06:06 > 0:06:10After three minutes, it's getting tougher to pedal the bike.
0:06:10 > 0:06:12Tim's VO2 is quite low at 20,
0:06:12 > 0:06:16but his heart rate is getting faster.
0:06:16 > 0:06:19- Heart rate's just creeping up towards 130, now.- Just slightly.
0:06:22 > 0:06:25After three minutes, Dean's heart rate is still amazingly low
0:06:25 > 0:06:28at only 89 beats per minute -
0:06:28 > 0:06:31that's over 40 beats slower than Tim's.
0:06:31 > 0:06:34His VO2 is the same as Tim's, at 20,
0:06:34 > 0:06:38but remember, an average 50-year-old should only be able to reach 32,
0:06:38 > 0:06:42and he's getting quite close to that already.
0:06:42 > 0:06:43All the data's showing me
0:06:43 > 0:06:46that actually Dean is finding this much easier than
0:06:46 > 0:06:48Tim was at the same point.
0:06:50 > 0:06:53You can hear the breathing deeper now.
0:06:53 > 0:06:56Tim's breathing is getting faster as his body tries to get as much
0:06:56 > 0:06:59oxygen as possible into his blood.
0:07:03 > 0:07:04Oxygen gets into your body
0:07:04 > 0:07:05through your lungs
0:07:05 > 0:07:07when you breathe in.
0:07:07 > 0:07:09The oxygen then moves into your blood.
0:07:09 > 0:07:11Your blood travels to your muscles, which use
0:07:11 > 0:07:13the oxygen in a chemical reaction
0:07:13 > 0:07:15with sugar to make energy.
0:07:15 > 0:07:17So the more your muscles move,
0:07:17 > 0:07:19the more oxygen they need.
0:07:23 > 0:07:27It's six minutes into the test and Tim is beginning to struggle.
0:07:27 > 0:07:29Channel your focus and keep going.
0:07:29 > 0:07:31You're doing really well.
0:07:32 > 0:07:36Keep you legs going. You need to keep the pace up, OK?
0:07:36 > 0:07:38Dean's VO2 is now at 32.
0:07:38 > 0:07:41This is the point where most 50-year-old bodies would
0:07:41 > 0:07:43start to max out with exhaustion.
0:07:43 > 0:07:45Keep going, Dean. Keep those legs turning.
0:07:45 > 0:07:47But Dean's body is still going strong,
0:07:47 > 0:07:51and his heart rate is remarkably low at 109.
0:07:51 > 0:07:54Dean's body is working really, really hard
0:07:54 > 0:07:58but he's still looking pretty comfortable in himself.
0:07:58 > 0:08:00Tim's heart is working much harder
0:08:00 > 0:08:03and has risen to over 140.
0:08:03 > 0:08:05He is working really, really hard.
0:08:05 > 0:08:07We can hear his breathing, we can see,
0:08:07 > 0:08:09ooh, heart rate's going up and up and up.
0:08:09 > 0:08:11The harder Tim makes his muscles work,
0:08:11 > 0:08:14the faster blood has to be moved round his body.
0:08:14 > 0:08:16This is done by the heart.
0:08:17 > 0:08:20Your heart is a pump that sits in your chest
0:08:20 > 0:08:22right between your lungs.
0:08:22 > 0:08:23Your heart pumps blood to your
0:08:23 > 0:08:25lungs, where your blood picks up
0:08:25 > 0:08:27lots of oxygen.
0:08:27 > 0:08:29This oxygen-filled blood then
0:08:29 > 0:08:30goes back to your heart to be
0:08:30 > 0:08:32pumped all round your body,
0:08:32 > 0:08:35to the muscles that need it.
0:08:35 > 0:08:37Eight minutes into the test
0:08:37 > 0:08:40and Tim's muscles are needing all the blood they can get!
0:08:40 > 0:08:45His heart rate is 172 beats per minute and his VO2 is 37.
0:08:45 > 0:08:48Now, remember, an average 36-year-old will have
0:08:48 > 0:08:52a VO2 of 45, before their bodies max out and they have to stop.
0:08:52 > 0:08:55I'm getting caught by your sweat.
0:08:55 > 0:08:59Eight minutes into Dean's test and his VO2 is at 43.
0:08:59 > 0:09:01This is 11 above the average for his age
0:09:01 > 0:09:04and he's still going strong.
0:09:04 > 0:09:06Dean's still not sweating.
0:09:06 > 0:09:09At this point I was getting splattered by Tim.
0:09:10 > 0:09:12Eurgh, OK.
0:09:12 > 0:09:14So, sweat is your body's way of cooling itself down.
0:09:14 > 0:09:17When your muscles use oxygen and sugar to make energy,
0:09:17 > 0:09:20the chemical reaction gives off a lot of heat.
0:09:20 > 0:09:22Your brain can tell that your body's getting hotter,
0:09:22 > 0:09:24so it starts trying to cool you down.
0:09:24 > 0:09:26So, it sends a signal to your sweat glands
0:09:26 > 0:09:28that are all over your skin
0:09:28 > 0:09:30and tells them to start sweating.
0:09:30 > 0:09:32You cool down because heat from your body,
0:09:32 > 0:09:34which was making you feel hot,
0:09:34 > 0:09:36is now used up to dry the sweat.
0:09:39 > 0:09:40Come on, well done.
0:09:40 > 0:09:43Keep the legs pumping. Pumping, pumping, pumping.
0:09:43 > 0:09:47It's nine and half minutes into the test and Tim's heart rate is
0:09:47 > 0:09:51at a critical 183 beats per minute
0:09:51 > 0:09:53and he's reached a VO2 of 45.
0:09:53 > 0:09:58This is the point an average body of his age gives up through exhaustion.
0:09:58 > 0:10:00Come on, Tim. You're racing yourself, now,
0:10:00 > 0:10:02no-one else, it's just about you. Keep going.
0:10:02 > 0:10:05- Another increase is coming up. Come on!- DEAN:- Come on, Tim.
0:10:05 > 0:10:07You can get through it. You can get through it.
0:10:07 > 0:10:09Keep going, keep going, keep going.
0:10:09 > 0:10:10MACHINE BEEPS
0:10:10 > 0:10:12Well done, well done.
0:10:12 > 0:10:18With a VO2 of 46 and a heart rate of 183, Tim has had enough.
0:10:18 > 0:10:21At just after the point Dr Megan predicted,
0:10:21 > 0:10:26Tim's body can't carry on, after ten minutes and ten seconds.
0:10:26 > 0:10:28Keep going, Dean, you're doing really, really well.
0:10:28 > 0:10:30Keep those legs pacing round.
0:10:30 > 0:10:33I know it hurts, but channel that. Use the pain.
0:10:33 > 0:10:35Nine and half minutes into Dean's test
0:10:35 > 0:10:38and his heart rate is at 156 beats per minute,
0:10:38 > 0:10:40and he has a VO2 of 46 -
0:10:40 > 0:10:44a staggering 14 above the average.
0:10:44 > 0:10:47- Keep going, Dean, keep going. - Dig in!- Keep going, keep going.
0:10:47 > 0:10:49Keep going, keep going.
0:10:49 > 0:10:50Keep the legs moving, keep them moving,
0:10:50 > 0:10:52keep them moving, keep them moving.
0:10:52 > 0:10:54It's really hard, this.
0:10:54 > 0:10:56But at this point, Dean's bike has had enough!
0:10:57 > 0:11:01After ten minutes, Dr Megan has to end the test.
0:11:01 > 0:11:03I think the RPMs wound down too slowly.
0:11:03 > 0:11:06The bike must have just shut down.
0:11:06 > 0:11:07The bike had had enough of you.
0:11:07 > 0:11:12So, at the end of the test, Dr Megan can tell Dean is no average human.
0:11:13 > 0:11:17After about ten minutes, Tim had reached his VO2 max of 46,
0:11:17 > 0:11:19one above the average.
0:11:19 > 0:11:22But ten minutes into his test, Dean had a VO2 of 50...
0:11:24 > 0:11:27..five higher than Tim's had been at the same point,
0:11:27 > 0:11:31and an incredible 18 higher than the average for his age.
0:11:36 > 0:11:39TIM: 'It is important to keep fit and healthy, but in some places
0:11:39 > 0:11:43'in the world, it can mean the difference between life and death.'
0:11:44 > 0:11:49The San people live in the Kalahari Desert in South Africa.
0:11:49 > 0:11:51When hunting, they run after their prey
0:11:51 > 0:11:54through some of the hottest and driest conditions
0:11:54 > 0:11:58on the planet until the animal collapses from exhaustion.
0:11:58 > 0:12:01These gruelling endurance chases can last
0:12:01 > 0:12:04over eight hours before the hunt ends.
0:12:04 > 0:12:07Our ancestors used the same method before weapons were invented,
0:12:07 > 0:12:10but it's so difficult that the San people are
0:12:10 > 0:12:13the last tribe on earth to hunt this way.
0:12:17 > 0:12:19For the second Super Test, Dr Megan, Tim and Dean
0:12:19 > 0:12:23have taken to the hills overlooking San Francisco Bay.
0:12:24 > 0:12:27In Super Test One, I was testing your heart and your lung function.
0:12:27 > 0:12:31For this one, I'm going to be looking at the muscles.
0:12:31 > 0:12:35Super Test Two is a race up this two kilometre long
0:12:35 > 0:12:37steep hill and will test how well
0:12:37 > 0:12:41Tim and Dean's bodies supply oxygen to their muscles.
0:12:41 > 0:12:43Halfway up the hill, Dr Megan will test them medically
0:12:43 > 0:12:46before they carry on to race to the top.
0:12:47 > 0:12:50When your muscles are going to get your body up that steep hill,
0:12:50 > 0:12:53they'll be requiring a huge amount of oxygen.
0:12:53 > 0:12:56Your heart and lungs are going to do their very best to get
0:12:56 > 0:12:59enough oxygen to the muscles, but at some point -
0:12:59 > 0:13:01and this will happen even for you, Dean -
0:13:01 > 0:13:02they just won't be able to keep up.
0:13:04 > 0:13:06When you exercise hard, you breathe faster,
0:13:06 > 0:13:09but eventually your muscles run low on oxygen.
0:13:09 > 0:13:12They start to hurt and feel like they're burning.
0:13:12 > 0:13:14You'll feel tired and dizzy.
0:13:14 > 0:13:16You might even faint or vomit.
0:13:16 > 0:13:19Eventually, your muscles will stop working all together
0:13:19 > 0:13:21and you'll collapse.
0:13:21 > 0:13:23OK, boys, now you're relaxed,
0:13:23 > 0:13:25I'm going to get your lactate levels, OK?
0:13:26 > 0:13:29As usual, Dr Megan will be monitoring them.
0:13:29 > 0:13:31She's measuring their heart rates,
0:13:31 > 0:13:35and also how much acid is in their muscles with a lactate test.
0:13:37 > 0:13:39This lactate test tells Dr Megan
0:13:39 > 0:13:42if there's not enough oxygen getting to their muscles.
0:13:42 > 0:13:45We always have some lactate in our bodies,
0:13:45 > 0:13:47so she needs to see what their normal levels are
0:13:47 > 0:13:50before the race, so she can see how much it goes up.
0:13:51 > 0:13:55- So your lactate when you're at rest, Dean, is 2.0.- 2.0.
0:13:55 > 0:13:57- Tim, 3.4.- OK.
0:13:57 > 0:14:01- So, Dean was 2.0, you were 3.4. - So I'm a bit higher than Dean.
0:14:02 > 0:14:05These results are what Dr Megan would expect from Tim and Dean
0:14:05 > 0:14:08before exercise, but she wants to see what happens
0:14:08 > 0:14:11to their bodies when they start running.
0:14:11 > 0:14:12TIM: You've got cold hands, doctor.
0:14:15 > 0:14:17OK, boys, I'll count you in.
0:14:17 > 0:14:21Three, two, one. Go!
0:14:25 > 0:14:28Both Tim and Dean start the race side by side,
0:14:28 > 0:14:30but as the hill gets steeper,
0:14:30 > 0:14:33Dean starts to break away from Tim.
0:14:34 > 0:14:37At this point, Dean's heart rate is only 140,
0:14:37 > 0:14:41while Tim's has shot up to 160 beats per minute.
0:14:42 > 0:14:47Tim's body is already starting to struggle as the race gets harder.
0:14:47 > 0:14:50Running uphill is tough on your muscles,
0:14:50 > 0:14:52and Tim's leg muscles are starting to hurt.
0:14:52 > 0:14:55This is because muscles hurt
0:14:55 > 0:14:57when they use too much oxygen.
0:14:57 > 0:14:59Your muscles use oxygen and sugars
0:14:59 > 0:15:01in a chemical reaction to make energy.
0:15:01 > 0:15:03But when you're exercising hard,
0:15:03 > 0:15:05your muscles use oxygen so quickly
0:15:05 > 0:15:08they run out, so they start to use
0:15:08 > 0:15:10the sugars by themselves.
0:15:10 > 0:15:12Now the chemical reaction
0:15:12 > 0:15:15creates energy and lactic acid.
0:15:15 > 0:15:17Although your muscles will still work,
0:15:17 > 0:15:19without oxygen they don't work as well.
0:15:19 > 0:15:23Eventually, the lactic acid causes pain in your muscles.
0:15:24 > 0:15:28After four and a half minutes, Dean reaches the halfway point.
0:15:28 > 0:15:32He's barely out of breath and he's smiling.
0:15:32 > 0:15:35- Well done, Dean. Borrow a finger?- OK.
0:15:37 > 0:15:39- OK, off you go.- Cool.
0:15:40 > 0:15:43But when Tim arrives a minute and a half later,
0:15:43 > 0:15:44he's not smiling.
0:15:44 > 0:15:46His muscles are burning and he's so out of breath
0:15:46 > 0:15:48he's barely able to speak.
0:15:49 > 0:15:52- Off you go.- OK.- Tissue?- OK.
0:15:53 > 0:15:55Oh, my goodness...
0:15:55 > 0:15:58Dr Megan is amazed by the results.
0:15:58 > 0:16:02After running for one kilometre, Tim has a lactate reading of 16.9,
0:16:02 > 0:16:04but the level of lactic acid in Dean's muscles
0:16:04 > 0:16:08is unbelievably low, at only 3.7.
0:16:13 > 0:16:15Eight minutes into the run and
0:16:15 > 0:16:17Dean is getting close to the top.
0:16:17 > 0:16:19His heart rate has risen by ten beats,
0:16:19 > 0:16:22to a comfortable 150 beats per minute.
0:16:24 > 0:16:26Tim is 250 metres behind Dean
0:16:26 > 0:16:29and his heart rate is beating dangerously fast,
0:16:29 > 0:16:31at 180 times a minute.
0:16:35 > 0:16:38After ten minutes and 45 seconds,
0:16:38 > 0:16:40Dean crosses the finish line.
0:16:40 > 0:16:42He still looks fine and his heart rate
0:16:42 > 0:16:46is only beating 151 times per minute.
0:16:46 > 0:16:48Dean! Amazing!
0:16:53 > 0:16:56Almost two minutes later, with muscles aching,
0:16:56 > 0:16:58Tim finally finishes.
0:16:58 > 0:17:03His heart is racing at a dangerous 184 beats per minute.
0:17:04 > 0:17:05You look like you're tired.
0:17:05 > 0:17:07Yeah, a little bit tired.
0:17:08 > 0:17:10So how does Dean do this?
0:17:11 > 0:17:14Dean's body doesn't make much lactic acid.
0:17:14 > 0:17:15This is because he's got more
0:17:15 > 0:17:17red blood cells than an average person.
0:17:17 > 0:17:20Red blood cells carry oxygen,
0:17:20 > 0:17:23so he has more oxygen in his blood than normal.
0:17:23 > 0:17:26He also controls how hard his muscles work,
0:17:26 > 0:17:29so they don't use up oxygen too quickly and run out.
0:17:29 > 0:17:32This means his muscles don't make much lactic acid
0:17:32 > 0:17:35when he's exercising, as they always have the oxygen they need.
0:17:35 > 0:17:37So Dean can run all day long,
0:17:37 > 0:17:40without suffering from painful muscles.
0:17:42 > 0:17:44TIM: I found that running challenge tough,
0:17:44 > 0:17:46but it's nothing compared to what happened
0:17:46 > 0:17:48to brothers Justin and Jeremy Harris.
0:17:50 > 0:17:52They were out hiking along a canyon
0:17:52 > 0:17:54in Utah in the USA
0:17:54 > 0:17:56when Justin slipped
0:17:56 > 0:17:58and broke his leg.
0:17:58 > 0:18:00With only hours left until dark,
0:18:00 > 0:18:02Jeremy ran for help,
0:18:02 > 0:18:04but he took a wrong turn down another cliff
0:18:04 > 0:18:05in the opposite direction.
0:18:05 > 0:18:08After an astonishing 20 hours
0:18:08 > 0:18:09running and hiking,
0:18:09 > 0:18:11Jeremy made it to a campsite
0:18:11 > 0:18:12and called for help.
0:18:12 > 0:18:14His refusal to give up and
0:18:14 > 0:18:16extraordinary ability to keep running
0:18:16 > 0:18:18saved his own life
0:18:18 > 0:18:19and that of his brother.
0:18:21 > 0:18:24For the final Super Test,
0:18:24 > 0:18:25Dr Megan, Tim and Dean
0:18:25 > 0:18:27have travelled to a desert
0:18:27 > 0:18:29called Death Valley.
0:18:31 > 0:18:33It's not for nothing this place is called Death Valley.
0:18:33 > 0:18:36It's one of the hottest and driest places on Earth.
0:18:36 > 0:18:39Even just standing out in the midday sun can kill a man,
0:18:39 > 0:18:42and I'm not going to ask the two of you to just stand,
0:18:42 > 0:18:43not even just walk.
0:18:43 > 0:18:45But I'm going to ask you run...
0:18:45 > 0:18:46all day.
0:18:46 > 0:18:48Run all day? Out here?
0:18:48 > 0:18:51- Can you do that?- I'm up for the challenge, you up for it?
0:18:51 > 0:18:53- Let's give it a go. - I've never even run a marathon.
0:18:53 > 0:18:55- Come on, guys. Let's try. - Let's do it.
0:18:55 > 0:18:59Dr Megan has marked out a three kilometre long course
0:18:59 > 0:19:01for Tim and Dean to run around.
0:19:01 > 0:19:03They will start running just after dawn,
0:19:03 > 0:19:05and will only stop when their bodies give up.
0:19:07 > 0:19:10Dr Megan wants to see how long they can run for and throughout
0:19:10 > 0:19:14the test she'll be checking that they're not in danger.
0:19:16 > 0:19:20The heat and the dehydration potential here in Death Valley
0:19:20 > 0:19:22poses a real risk of heat stroke,
0:19:22 > 0:19:23a potentially fatal condition.
0:19:23 > 0:19:26If at any point either of you feel you can't continue,
0:19:26 > 0:19:29or I think you're in critical danger,
0:19:29 > 0:19:30the test ends then and there.
0:19:30 > 0:19:31- Yep.- OK.
0:19:33 > 0:19:35Doctor Megan has a medical team on stand by,
0:19:35 > 0:19:38plenty of hydration drinks and a cool room
0:19:38 > 0:19:42should the heat get too much for Dean and Tim.
0:19:42 > 0:19:45This does not sound fun. Why do you do it?
0:19:45 > 0:19:46There's magic in misery.
0:19:46 > 0:19:48It'll be a lot of misery, but there's some magic in it
0:19:48 > 0:19:50and I think you'll experience that today.
0:19:52 > 0:19:54Think the two of you are ready to go?
0:19:54 > 0:19:56It will be challenging, but I think we can do it.
0:19:56 > 0:19:58- Let's give it a try, let's go.- OK.
0:19:59 > 0:20:02Throughout the test, Doctor Megan will be
0:20:02 > 0:20:05closely monitoring Tim and Dean's heart rate and lactate levels.
0:20:10 > 0:20:13OK, so I'm out here in a place so hot you can fry and egg on a rock.
0:20:13 > 0:20:16I've got my special hat, my special glasses
0:20:16 > 0:20:19and I'm going to try the longest run of my life against you.
0:20:19 > 0:20:22- OK, boys, are you ready to go?- Right.
0:20:22 > 0:20:26Three, two, one,
0:20:26 > 0:20:27off you go!
0:20:30 > 0:20:31Woo-hoo!
0:20:43 > 0:20:44Halfway through the first lap,
0:20:44 > 0:20:46Dean's heart rate's going
0:20:46 > 0:20:47about 117 beats a minute.
0:20:47 > 0:20:48Feeling comfortable?
0:20:48 > 0:20:50- That was a good warm-up lap! - You go, Dean!
0:20:50 > 0:20:52Making this look extremely easy.
0:20:57 > 0:20:59Tim, on the other hand,
0:20:59 > 0:21:01heart rate now 172.
0:21:01 > 0:21:04I mean, it is steaming hot here.
0:21:04 > 0:21:07In fact, even at 8.15 in the morning, it's already
0:21:07 > 0:21:10an incredible 32 degrees centigrade.
0:21:10 > 0:21:15That's hotter than a really boiling summer's day in the UK.
0:21:15 > 0:21:17Tim, you are doing really well!
0:21:17 > 0:21:18Is there anything you want me
0:21:18 > 0:21:21to have ready for you when you get past?
0:21:21 > 0:21:23Liquid. OK, so if you saw that,
0:21:23 > 0:21:27Tim can't even talk to me to tell me. He's having to demonstrate.
0:21:28 > 0:21:32I don't expect you to talk to me but I'll just run along with you.
0:21:32 > 0:21:35You're doing really, really, really well. It is steaming hot.
0:21:35 > 0:21:38I think we should have made this one a relay.
0:21:38 > 0:21:41- Take it slow and steady and keep going.- OK.
0:21:42 > 0:21:44Tim's able to hold a conversation with Dr Megan,
0:21:44 > 0:21:47so even though his heart is beating extremely fast,
0:21:47 > 0:21:51at 172 beats a minute, she's happy to let him continue.
0:22:00 > 0:22:03He still seems fresh. It's extraordinary!
0:22:12 > 0:22:14Are you able to pause for a second
0:22:14 > 0:22:18- for me to do a lactate? - Yeah.- Fantastic.
0:22:18 > 0:22:19Comfy, happy?
0:22:19 > 0:22:22Yeah, I mean, it usually takes about four or five hours
0:22:22 > 0:22:26- for me before I start feeling like I'm actually going, so...- OK.
0:22:26 > 0:22:29Thank you for checking on me, though. You're doing a great job!
0:22:31 > 0:22:33With two laps in, Dean's chatting to me completely normally
0:22:33 > 0:22:38and comfortably and phenomenally his lactate level is 3.3.
0:22:41 > 0:22:42After nearly an hour,
0:22:42 > 0:22:44for Tim it's a different story.
0:22:44 > 0:22:48With a heart rate of 182 beats per minute, he's obviously
0:22:48 > 0:22:52struggling, and Dr Megan is beginning to get a bit worried.
0:22:55 > 0:22:57Tim is barely moving.
0:22:57 > 0:22:59We've got the medical van just metres behind him.
0:22:59 > 0:23:02You can see Dean sprinting off into the horizon.
0:23:02 > 0:23:06I know from all the monitoring we've got on Tim his heart is
0:23:06 > 0:23:08working as hard as it can.
0:23:08 > 0:23:11The reason he's really not being able to run is his muscles
0:23:11 > 0:23:14are just swimming around in a pool of acid. Poison.
0:23:14 > 0:23:16Dean said to me that as he passed Tim he spoke to him,
0:23:16 > 0:23:18and he thought Tim was delirious.
0:23:18 > 0:23:21That means Tim is no longer making any sense,
0:23:21 > 0:23:22he's just talking nonsense.
0:23:22 > 0:23:24I'm pulling him.
0:23:28 > 0:23:31Tim, I've had a look at all the observations and we've had
0:23:31 > 0:23:33a chat with Dean and I'm no longer happy for you to continue.
0:23:33 > 0:23:36This is not safe any more, so I'd like you to stop here.
0:23:36 > 0:23:38Get your arms up. Keep them up, keep them up.
0:23:39 > 0:23:43Tim has had to stop running after one hour and 15 minutes.
0:23:44 > 0:23:47His lactate level has doubled since the start of the race
0:23:47 > 0:23:52and his heart is dangerously fast, at 182 beats per minute.
0:23:53 > 0:23:56He is sweating and in pain,
0:23:56 > 0:23:59and Dr Megan wants to get him into the recovery vehicle.
0:23:59 > 0:24:02This is a nice cooled van to help with your recovery.
0:24:04 > 0:24:07Outside the cooling room, Dean is still running
0:24:07 > 0:24:09and making it look easy.
0:24:09 > 0:24:12He still hasn't even broken a sweat.
0:24:12 > 0:24:15It is really fascinating to see. His lactate level,
0:24:15 > 0:24:17at the point at which I pulled you -
0:24:17 > 0:24:19so he'd done the same number of laps as when
0:24:19 > 0:24:20I pulled you from the test -
0:24:20 > 0:24:22was still only 3.3.
0:24:22 > 0:24:24Wow! Just look at the state of me!
0:24:24 > 0:24:27And he's got the same lactate levels as I would have
0:24:27 > 0:24:29if I was just in my bedroom.
0:24:29 > 0:24:30That's extraordinary.
0:24:34 > 0:24:35At 10.20, the temperature has
0:24:35 > 0:24:39already reached 37 degrees Celsius.
0:24:39 > 0:24:41The sun is now so hot
0:24:41 > 0:24:44that instead of taking off clothes to cool down, Dean has put on
0:24:44 > 0:24:48some special lightweight clothes to cover up to avoid sun burn.
0:24:57 > 0:24:59It's ten past one and Dean's been
0:24:59 > 0:25:01running for over five hours,
0:25:01 > 0:25:04but his spirits are showing no signs of dampening as he starts
0:25:04 > 0:25:06a water fight with one of the film crew.
0:25:07 > 0:25:10Got to have some fun, right?
0:25:18 > 0:25:20Keep going, Dean!
0:25:20 > 0:25:21Looking good, looking good.
0:25:21 > 0:25:23Unbelievable.
0:25:23 > 0:25:25Over seven hours in,
0:25:25 > 0:25:29forty degrees in the shade, and the man's running in the sun
0:25:29 > 0:25:31and he hasn't even broken into a sweat.
0:25:31 > 0:25:32Amazing.
0:25:40 > 0:25:41How do you get yourself mentally
0:25:41 > 0:25:43to keep going through that?
0:25:43 > 0:25:46I'm superhuman. We don't tire.
0:25:46 > 0:25:481.3. His lactate's 1.3.
0:25:51 > 0:25:55Incredibly, Dean's lactate level is now half of what it was
0:25:55 > 0:25:57before he started running.
0:25:57 > 0:25:59And remember, Tim ran for just over an hour
0:25:59 > 0:26:02and his doubled from 2.8 to 5.6.
0:26:05 > 0:26:06I was out here running
0:26:06 > 0:26:07for one hour 15 minutes.
0:26:07 > 0:26:09Dean? He's still out here.
0:26:09 > 0:26:12He's been running for over nine hours.
0:26:12 > 0:26:14That's like you get up in the morning, you have breakfast,
0:26:14 > 0:26:15Dean is already running.
0:26:15 > 0:26:17You have lunch, Dean is still running.
0:26:17 > 0:26:19You have your evening meal, Dean is still running.
0:26:19 > 0:26:21And he's still going.
0:26:21 > 0:26:24He doesn't seem remotely bothered by this incredible heat.
0:26:29 > 0:26:32It's six o'clock in the evening and Dean has been running
0:26:32 > 0:26:35for ten hours in the unbearable heat of Death Valley.
0:26:35 > 0:26:40He has covered an astonishing 86 kilometres, he's not sweating
0:26:40 > 0:26:42and he's not even tired.
0:26:44 > 0:26:4686 kilometres, Dean.
0:26:46 > 0:26:47I think it's time to call it a day.
0:26:47 > 0:26:49I could keep going if you want me to!
0:26:49 > 0:26:53I feel strong. I feel like I still have some gas in the tank.
0:26:53 > 0:26:56That's absolutely incredible. You've done nearly 90 kilometres,
0:26:56 > 0:26:58and you could just keep going.
0:26:58 > 0:27:00It's phenomenal, Dean. Your lactate's still 1.3.
0:27:00 > 0:27:03That's less than a normal person at rest.
0:27:03 > 0:27:04You've not broken into a sweat.
0:27:04 > 0:27:06I have never witnessed an athlete like you.
0:27:06 > 0:27:08I'm just out here doing what I love.
0:27:08 > 0:27:11TIM: I came to the USA to find a real life superhero,
0:27:11 > 0:27:15a man, it seems, that can run for ever.
0:27:15 > 0:27:16I found one.
0:27:16 > 0:27:21Dean Karnazes, you are Super Human.
0:27:22 > 0:27:24It's been a real honour running slightly behind you.
0:27:24 > 0:27:26Tim, the honour's all mine.
0:27:26 > 0:27:29I think you are heroic for coming out here in these
0:27:29 > 0:27:31very dangerous conditions and doing what you did.
0:27:31 > 0:27:34- Let's do it again.- Oh, no!
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