[Other Sport] Chris Froome cleared over Vuelta drugs test - case dropped

Harry Wilson's tackle said:

Interesting thread. Some comments

1. Salbutamol ('chemical' name) is Ventolin (trade name) like 'crisps' and 'Golden Wonder'.

2. It is a beta2 agonist which means it mimics the effects of the body's adrenaline (a blood borne chemical) or noradrenaline (a similar chemical released from 'sympathetic' nerves) on the beta2 receptor. This is one of several receptors located in different bits of the body that respond in different ways to 'sympathetic' agonists (the others are alpha1 which leads to blood vessel constriction, and beta1 which leads to an increase in the rate and force of the heart, among other things).

3. No agonist is completely selective so althouh salbutamol is 'beta2 selective' it can, at very high dose, cause some activation of beta1 receptors. Heart rate and cardiac output would then increase. If this occurs it is arguably 'performance enhancing' which is probably the reason for the rules about dosage. Personally I doubt there is much of an effect even at 'heroic' dosage and I wouldn't consider taking salbutamol of I wanted to increase my indurance. Increased heart rate (tachycardia) would be a side effect of overdosage, and it would be accompanied by dizziness and feeling unwell - of no use to a cyclist.

4. There are beta2 receptors in the arterioles leading to skeletal muscle. Thus in theory salbutamol might increase blood flow to the cycling muscles - performance enhancing. However this is unlikely to be remotely relevant because a cyclist will have his skeletal muscle arterioles maximally dilated during and due to the exercise of cycling (this is called hyperaemia and is a natural process - exercising muscles have increased blood flow). There is a condition called 'Claudication' (named after the limping Roman emperor, Claudius) where there is a fixed obstruction of a large vessel leading to a muscle in the leg. This makes the muscle lose blood flow and become weak (ischaemic). Drugs can be given that dilate the muscles arterioles (including beta2 agonists). However blood flow does not increase because these vessels are already maximally dilated (due to the upstream restriction making the miscle hypoxic/ischaemic), but not receiving extra blood because of the upstream obstruction of the main artery. I mention all this to illustrate the difference between theory and practice. In theory a beta2 agonst could increase sketal muscle blood flow. In practice the effect, if any, is hard to obtain at safe dosage, and is effectively irrelevant.

5. As an aside, a clownish GP thouht I had developed asthma (at the tender age of 59 - it doesn't happen) when I had respiratory issues and prescribed me Ventolin. It had absolutely no effect (because my respiratory tubes were already dilated). A week later, a smarter GP diagnosed a lung full of fluid (mild pneumonia) and gave me some drugs that actually worked.

6. Salbutamol is metabolized in the liver so I am not sure why tests are done to detect it in the urine (I have looked this up and remain confused). I would have thought the tests would be to detect the metabolite. Drugs primarily eliminated in the urine will hang around longer in the blood during extreme exercise due to the fact that blood flow to the kidney falls during heavy exercise (redirected to skletal muscle). I would have thought that the only reliable estimate of salbutamol in the blood would require a blood sample. Anyway...

Does Broome have actual asthma? If he does then there is nothing to see here. If not, he (or someone in his team) is being silly, but no more silly than getting the lad to drink litres of herbal tea.

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Triggaaar said:

I think Ventolin is just a brand of salbutamol. I know what it's supposed to do, my daughter has it had it since she was a baby. What I didn't realise back then was that so many top sportsmen use it.

Is it simply that a very large percentage of the population has asthma to some extent, but doesn't realise it as we're not pushing our bodies?

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Thunder Bolt said:

My other half is severly asthmatic, and has been since he was five years old. I've seen him struggle to breathe, and have to take Ventolin, just so he can exhale. It's not even the most important drug he has to use, as the steroid inhaler Seretide is vital as a preventative measure (see also Becatide).

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Saunders said:

Sorry to hear that, the times I have that I struggle to breathe are in the middle of the night. I dont know how to describe the feeling of waking up and not being able to breathe (I cant inhale) and trying not to panic to make it worse. Yes I have taken the steroid one myself and didnt get on with it. I would imagine sportsmen cant use the steriod one to manage their asthma better so have to rely on dealing with bad days as soon as they can with what they are allowed. Thats what makes this all the more bizarre.

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Stat Brother said:

Because it's not a performance enhancing drug, there is a limit because there has to be a limit.
Personally I hope this case is used to clear up the very grey area of TUEs, but as said if this is the worst cycling has got (sadly it isn't but you know what I mean) then the sport is in considerably better health, pun intended.

All very different to injecting EPO supercharged blood into your system, having had it cleaned in Madrid and couriered to you on rest days.

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