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  • So you see what I don't understand is

  • why I have to go through all this pain.

  • But when I do see something I don't agree with

  • I become addicted to try to answer what is the truth.

  • Today I'm going to talk about some of the ideas

  • that I've focused on.

  • They come in many different topics

  • and you can see they cover

  • medical problems in marathon runners.

  • Rugby injuries. Are all rugby players overplayed?

  • Something about nutrition.

  • Should we be eating carbohydrates

  • or should we be eating fats?

  • And particularly what regulates our exercise performance?

  • And then, is it possible to swim at the North Pole

  • at -1.8°C in a speedo?

  • So I'm going to talk about those questions

  • and I'm going to begin by the very first question

  • that ever came to me as a scientist was:

  • Are marathon runners immune to heart disease?

  • And this was a theory developed

  • by a Californian pathologist

  • and he said on the basis on any contrary evidence,

  • it looked like if you ran a marathon

  • you'd never have a heart attack.

  • So I mean I knew that it was absolutely bogus

  • but to prove it was all the more difficult.

  • At the time in the 1970s

  • this was the bible of running.

  • It was written by James Fixx

  • and he described at length the whole hypothesis.

  • Tragically seven years after this picture was taken

  • James Fixx died of a heart attack while running.

  • But by then we had in fact already shown

  • that it was possible for people to have heart disease.

  • So we looked for when we saw reports of people

  • dying in marathon races

  • we would go and collect their hearts

  • and we would examine them

  • and eventually we found the evidence

  • and so we published a paper

  • in the New England Journal of Medicine

  • showing that there were runners who had disease

  • and the disease here is -- this is coronary artery disease

  • in which there's obstruction of the coronary arteries

  • causing heart attacks and we were able to show

  • that this man had had a heart attack whilst

  • he was running a marathon.

  • So that was published and so that disproved

  • that's obviously very easy to do, it's easy to find a few cases

  • that disprove a theory.

  • The next one that I really got involved with

  • is in the 1980s was:

  • Should we be drinking more or less during exercise?

  • And at the time in the 1960s

  • it was held that actually if you drank during exercise

  • that wasn't a very good idea.

  • Abebe Bikila who was the first African runner

  • to win two Olympic gold medals

  • in the 1960 and 1964 Olympic marathons

  • he ran both races without drinking anything.

  • That was what runners did in those days.

  • And then all of a sudden in the 1960s and 1970s

  • things changed and we were told that

  • if you didn't drink enough, you were going to die during exercise.

  • I became interested in why that would be the case.

  • And the epiphanous moment occurred on 1 June 1981

  • when an athlete started the Comrades Marathon in Bourbon

  • and she reached 70 km

  • and her husband withdrew her from the race

  • because she didn't recognise him

  • and he felt that wasn't a good idea. (Laughter)

  • And he then took her for medical care

  • and in short order within two hours

  • she was unconscious having epileptic seizures,

  • and she had to be taken back to hospital in Bourbon.

  • And when she was admitted to hospital

  • she became the first case of this condition

  • which -- a long name we don't need to understand

  • what it is at the moment.

  • But here's her chest x-ray and this shows

  • that she's got fluid in her lungs

  • and it took five days later

  • before the fluid had gone out of her lungs

  • but this is what happened what really happened

  • was that her blood sodium concentration

  • which should normally be at 140 and is tightly regulated,

  • it's one of the most regulated features of the body

  • had dropped to 114 that's heroically wrong,

  • something had gone tragically wrong

  • and she asked me what had happened

  • and I said, "We have absolutely no idea."

  • and it was the first case in the world

  • so we had no idea.

  • Over the next four or five years

  • we picked up couple of more cases and

  • worked out that they probably had overdrunk

  • and in other words

  • they'd drunk too much during exercise.

  • And then at the 1988 Comrades Marathon

  • we could prove it by hospitalising eight people

  • who were really sick with this condition

  • and follow them during their recovery

  • and we were able to show

  • that they all passed an excess of fluid

  • during recovery and so this athlete here

  • passed six litres of fluid extra during recovery

  • and that she had dropped her blood sodium concentration

  • to a very low level

  • and you can see there was a nice relationship.

  • So the more you overdrink

  • the lower your sodium

  • and the sicker you were

  • and we published that in 1991

  • and thought that's the end of the problem.

  • We cured the problem,

  • we know what causes it, it's overdrinking

  • and we thought the problem would go away.

  • But unfortunately at the same time we were doing that,

  • industry would come along and said,

  • "No actually, the more you drink, the better."

  • So there's an advert

  • saying that not only must you drink

  • but you must drink heroically during exercise

  • this is 1.2 litres per hour

  • or your performance will suffer.

  • And we predicted what would happen,

  • we predicted this would happen.

  • And this is the incidence of this condition

  • accumalative incidence of this condition

  • which had never existed before 1981, never existed

  • There were a total of 1600 cases in the medical literature

  • this is not all cases because many were not recognised

  • and tragically twelve deaths,

  • all completely avoidable.

  • And so what happened was that

  • the sports drink industry came along then

  • and then they influenced the official drinking guidelines

  • drawn up by official bodies

  • and those promoted overdrinking.

  • Then a lady died in the Boston Marathon in 2002

  • and in 2003, I was invited by two organizations

  • to produce alternate drinking guidelines

  • which promoted drinking to thirst

  • and that finally has now been accepted that

  • that is the way we should be drinking.

  • But you can see what the cost of that disease

  • that had never existed came along.

  • And finally the book written about

  • the whole sorry thirty-year saga

  • was released recently.

  • And what I was able to show was that

  • the science of hydration is utterly bogus.

  • There is no science to it,

  • it was dreamed up by marketers to sell a product

  • and I'll come back to that point in due course.

  • The next question that really has intrigued me was:

  • Do muscles regulate exercise performance

  • or is it something else?

  • And it's really interesting in sport that you see

  • such close finishes.

  • And this was the 2000 ten thousand meters in the year 2000

  • and you can see that Haile Gebrselassie has won this race

  • by a few inches

  • and it's a race that goes on for twenty-five minutes,

  • so how can a twenty-five-minute race

  • come down to a few centimeters?

  • And the argument is that the reason why the athlete

  • comes second is because his muscles

  • offers too much lactic acid

  • and that causes him trouble

  • so the athlete who comes second,

  • his heart is unable to pump enough blood to his muscles

  • so they become anaerobic and

  • as a consequence they produce lactic acid

  • which you all learned in biology

  • causes muscle poisoning and stiffness

  • and everything that goes wrong in sport

  • is a related to this terrible product lactic acid.

  • Over time, it took us a few years

  • but we realised this model can't be right

  • it can't be true

  • for a very simple reason.

  • That it's brainless.

  • Fatigue in this model is caused exclusively

  • by the failing muscles.

  • So the brain can't influence your performance.

  • So what you think is utterly completely irrelevant.

  • All of you know that's rubbish

  • because motivation must have a role

  • in some way in sporting performance.

  • So we did a lot of research

  • and then finally we realised what the evidence was.

  • Again it just takes one insight to see these things.

  • This is Haille Gebrsellasie running 10 000 meters.

  • This is his average pace for each kilometer

  • and what do you notice?

  • He runs the fastest the last kilometer.

  • But how can that be?

  • How can he run his fastest when he's most fatigued?

  • And all that tells you is that fatigue

  • as we describe it

  • has got nothing to do with the physical side of your body

  • because he's performed much better

  • when his muscles are the most tired.

  • So therefore we worked out that fatigue is purely an emotion

  • it's what your brain is making up

  • it's completely fallacious

  • emotional information that your brain uses

  • to make sure that you don't die during exercise. (Laughter)

  • And so we eventually came up with this model

  • the Central Governor Model of Exercise

  • which originally was critizised

  • when we proposed it in 1996.

  • People said, "You're mad! How can it possibly be true?"

  • I'm glad to say that there are multiple Olympic athletes

  • at this very moment training according to this model

  • and acknowledging it

  • that they are now training

  • because they understand performance.

  • And what this model says simply is that

  • the brain regulates your muscle performance

  • and that feeds back to your brain

  • and then there are other factors like

  • motivational factors and I see my time is running

  • so I'll have to go a bit quickly.

  • That there are a whole bunch of factors

  • that influence your brain

  • and then you start exercise at a particular work rate

  • which is different depending on how far the activity is.

  • You always have reserves

  • you always finish with,

  • you could always exercise harder.

  • There's always an end spurt

  • and finally, there's always feedback to the brain.

  • So that's the way the system works.

  • And as I've indicated

  • it's now becoming accepted.

  • The next question:

  • Is it possible to swim 1 km at -1.8°C

  • in only a speedo?

  • The person who asked me that question was Lewis Pugh.

  • We, just approximately five years ago

  • travelled to the North Pole

  • to swim have him swim 1 km

  • and I had to make sure he returned alive.

  • It all began when he said,

  • "Can I swim around the Cape Peninsula?"

  • and I said, "Yes"

  • and everyone else had said, "No. That's impossible."

  • So he went out and swam around the peninsula.

  • It took him thirteen days

  • but he managed to do it.

  • And when he finished he said

  • "Can I now go and swim at the North Pole

  • or in the Arctic where the temperature is 0 to 5°C?"

  • and I said, "I can't guarantee that you'll live."

  • However, fortunately, there's a picture of him diving in