We put this question to Professor Chris Cooper:

That’s a really interesting question.  There are natural steroids.  Testosterone is a natural steroid and obviously men have more of that than women do.  It’s illegal to take testosterone because it’s not part of your normal diet.  You can’t get a diet equivalent to fail a drugs test.  It’s difficult to take a steroid in any normal diet to have an effect because they don’t work orally. You have to inject them, then it’s obvious you’re doing the cheating.

Where it’s a more grey area is in some of the metabolites the body makes from these artificial compounds which are also illegal because the agencies say that means you’ve taken the metabolites.  There’s a concern that if you exercise very hard on certain diets you might make small amounts of these metabolites naturally.  Then it’s a question of what level the drug company sets those out.  It’s difficult to take the natural compound to fail a drugs test.  The bodies make it that way.  They don’t want to fail people for that.

We put this question to Professor Chris Cooper:

The cynical answer is to say we know that because we have Tim Montgomery as an example of somebody but then he’d been beaten by Usain Bolt!  I think it’s quite a difficult question to answer.  The world record now is 9.72 [men’s 100m] and no evidence that’s been done illegally.  You can sort of extrapolate form that where you might get.  I think increasingly we’re going to see genetic anomalies, people who’ve got a genetic aberration that makes them perform better and that’s going to be what makes the difference.  A classic example was a Finnish cross-country skier who had a naturally active EPO system.  He made in his body large amounts of red blood cells because he had a gene defect.  It wasn’t a defect, of course!  I think you’ll see these step changes by people who happened to have had a mutation.  It’s difficult to therefore extrapolate.

The answer to this is it’s a totally different fuel source.  The fuels totally differ in the way in which they behave inside the engine.  Petrol engines have spark plugs and diesel engines don’t.  That’s the simplest difference. 

In a petrol engine what happens is you have the piston going down in the cylinder.  It pulls in some air and at the same time some fuel is added - sprayed in if you have an injection engine, or just drawn in with the air if you have a normally aspirated engine.  

The next thing that happens is that the piston goes up again and it compresses the mixture of petrol and air.  This makes it a bit warmer because when you compress things they do heat up but it doesn’t make it hot enough to ignite the petrol.  Just before the piston gets to the top of the cylinder the spark plug kicks in, ignites a spark which ignites the fuel-air mixture.  This burns very fast and this turns a liquid into a gas which takes up many, many times more space.  This increase in volume inside the cylinder drives the piston back down inside the cylinder creating power.  That’s the power stroke.  On the way up again the exhaust valves open and you blow the exhaust out.  That’s how a petrol engine works.

With a diesel engine the difference there is that you’re entirely depending on the compression of the engine to make the explosion happen.  What happens is the piston goes down.  If you’ve got a normal, old fashioned diesel engine like they used to have on tractors and things this just drew in a cylinder full of air above the piston: a bit like you pulling on a syringe and filling a syringe with air.  The next thing that happens is that the piston would go up and as the piston goes up it compresses the air that it’s drawn in.  If you’ve got a turbocharger on your engine actually what happens is it forces a bit more air into the cylinder under pressure.  You have more air than you would normally have in the cylinder.  As the cylinder comes up it compresses all of the air and when you compress air (just like putting your thumb over the end of a bicycle pump) it gets very, very hot.  The heat is hundreds of degrees Celsius and just at the top of the piston compressing the air, right at the top of the cylinder, the fuel pump turns on and it sprays a fine mist of diesel fuel into this superheated air right at the top of the cylinder.  This mist of diesel immediately starts to burn and just like the petrol engine it produces enormous amounts of gas.  This expands very rapidly and that’s what produces the power stroke.  No spark plugs in a diesel engine.  That’s basically, in a nut shell, the difference.

We put this question to Professor Chris Cooper:

It’s kind of like the athlete having a biometric passport that says they’re all the same level and treating them like a formula one car.  Something of the sort is used in cycling and in cross-country skiing where if you have too many red blood cells you can’t compete because it’s assumed it’s unsafe.  You might have a heart attack.  You’re not banned.

Chris Smith -  In reality someone’s probably just banked a unit of blood a few months ago, built their blood back up and then re-infused it before the big race to boost their oxygen capacity before the big race?

Chris Cooper -  Yeah, but if you set the level low enough then they will fail.  That’s the trick, to set it at a fair level.

We put this question to Professor Chris Cooper:

There’s always claims.  Ben Johnson always thought that’s what happened to him.  It’s not clear it was.  Dieter Bowman, a famous West German runner, claimed he was drugged in his toothpaste.  There was some evidence that was the case.  If you’re running a marathon you always take your own drink and it’s always sealed.  You don’t take drinks that are lying around, people are concerned about it.

We put this question to Professor Chris Cooper:

There are certainly some people who’ve claimed that.  I’m reminded of this great true story about one of the Olympic 100m sprinters who failed the test John talked about – too much testosterone.  In his defence he said it was his wife’s birthday so he had to have sex five times the night before and that’s why his testosterone was so high. He got off!

Chris Smith -  In more ways than one!

Chris Cooper - Yes, anyway, yes!

Chris Smith -  Is that true?

Chris Cooper - The story is true.  I think testosterone can vary depending on whether you’re having sex or not.  Not by the amount he claims.  I don’t think you can use it as a performance enhancing effect.  It might not be a good idea the night before a race.

We put this question to Professor Chris Cooper:

Clearly it is faster for you because you’ve just given us the scientific evidence that you feel you do run faster when you’re in bare feet.  I don’t think in general running barefoot is faster.  The historical example is Zola Budd who is South African and came to run for England.  She ran as fast to begin with barefoot and she would have been much worse running in shoes because she wasn’t used to running in shoes.  I think your kind of event that’s fine if someone doesn’t step on you when you’re running.  The sprinting events I think shoes are really important.  I would be really surprised if you had 100m barefoot as fast as you could without.

Chris Smith - As we heard from Meera talking to the Loughborough team showing that you get far more force produced because of the ankle articulation because of the stiff shoe compared with barefoot or even a pair of trainers that are fairly soft.

Dave Ansell -  Maybe he might be wearing very bad shoes which are slowing him down.

Chris Cooper - Yes, that’s another thing. Get another pair of shoes!

We put this question to Professor Chris Cooper:

That’s an interesting question.  There’s always scare stories about what’s in my water, what harm is it doing?  There’s a long-term slight concern about female hormones getting into the water at very low levels.  It’s not likely to be a big health problem but there have been concerns in the past.  In terms of drugs and sport there’s no way you can get enough drugs for you water supply to help with sport or to fail a drugs test.  The small part of that question is not a problem.  The general human health point is a whole other major issue which I think is probably overstated but it is out there.