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Wednesday, April 10, 2013

The thyroid medication debate: Is it doping? Brief thoughts

Does the use of thyroid stimulating hormones in athletes cross a doping boundary?

Early today, I tweeted a link to a really thought-provoking investigative piece from the Wall Street Journal.  It describes a USA-based doctor, Jeffrey Brown, who treats a number of athletes for hypothyroidism, which he describes as a condition that afflicts endurance athletes as a result of their high training volumes and intensity.  It's an excellent article, and well worth a read before you read on.

Without going into every single intriguing question raised by the article (there are many - the validity of his claim that hypothyroidism is common among athletes is questioned, as is the performance benefit of the drug), I thought I'd share some very brief thoughts on it below.  This is, as always, a first word on a debate and I welcome thoughts and comments below!

Brief comment

When reading about the medical use of drugs in athletes, the most obvious and impulsive parallel to draw is asthma, for which athletes can get TUEs (therapeutic use exemptions) to use steroid-containing inhalers to restore "normal" function and compete fairly.  It's been suggested that within the athletic population, the prevalence of asthma is higher than in a typical sample, and that's not a triumph over adversity, it's more likely the manoeuvring of athletes within the grey areas of doping control!  The same is true for some other drugs - Armstrong's corticosteroid TUE in 1999 comes to mind.  Lionel Messi and HGH as a child is another.

With thyroid hormones, however, I feel that the situation is subtly different, because the allegation (in the WSJ article, anyway) is that it's the training that causes the condition to begin with.  That's not the case for asthma, which is an existing condition, admittedly worsened by intense exercise, but not a direct consequence of exercise participation and training.

In effect then, in the case of hypothyroidism, the athlete requires the medication because they behave as an athlete - they train hard.  They generate the condition, and the drug permits harder training, and that to me does cross the line of fairness.  I see no distinction between this and the use of testosterone or other hormones to ensure that recovery is optimized.  Similarly, blood doping or other methods to manipulate blood could be justified as means to help the body recover from the arduous training required to compete as an elite athlete.  After all, the chronic effects of a three-week stage race like the Vuelta Espana on hormones are known - for instance, testosterone and cortisol decrease significantly - this is the result of the stress of competition.  These changes could arguably be treated, with valid and credible physiological benefits, by the administration of drugs.  I do not see the difference between this situation and the use of any other medication that directly stimulates hormone production by the body.

Of course, this introduces a slippery slope, one that those of you well versed in the doping debate will be onto right away.  If these types of interventions are banned, then why not similar interventions that improve recovery, including diet?  This is where the debate gets progressively greyer, and in lecturing students today, it came up as a very important question.  It's not a leap of logic to go from a position that allows some things to allowing everything, or vice-versa - if you can't use X, then you shouldn't be allowed to use Y.

I have no definitive answer on this, only an opinion.  That is the opinion that part of becoming a world-class athlete is the ability to respond to high training volumes.  In an almost "Darwinian" manner, training is the stress that sorts out the fittest from the fitter (the fit and unfit have long ago been filtered out by performance level and lack of, for want of a better word, talent!).

Therefore, if an athlete is subjected to a training load X and intensity Y, their ability to respond to that load with improved physiology and performance, without breaking down sick, overtrained and injured, is crucial for their ultimate performance level.  If they cannot adapt, and break down, they become sick and overtrained, and fail to reach the same levels as the responders.  The athletes who require medical assistance that nudges their hormones levels up to restore them to levels typical of a non-training individual are benefitting from an unnatural practice that DIRECTLY changes hormone levels.

Of course, I must stress that the aetiology and presence of the hypothyroidism introduced in the WSJ article (link below for more) is debatable to begin with, but it would seem to me to be part of the giant complex puzzle that goes into producing an elite athlete.  It's also debatable whether the administration of thyroid stimulating drugs benefits performance.  One IOC source quoted in the WSJ piece claims that it is more likely to inhibit than enhance performance, and so clearly studies are required.  Studies are also required to understand if it is harmful.  However, in principle, I cannot see how the prescription of synthetic thyroid hormones to help athletes cope with training differs from the administration of steroids and blood-manipulating drugs and methods that are already on the list of banned substances and practices.

I'm sure there will be widely differing opinions, and I welcome them all.  I'm certainly well aware of the "hypocritical" position one can adopt when saying one practice should be banned but not another.  Indeed, we've had the debate about the legalization of drugs in sport many times right here.  This is yet another grey area in that debate.  Your thoughts are welcome.

For a start, the thoughts shared here by Letsrun.com's Weldon Johnson are interesting, well framed and include quotes from inside the sport of athletics.  They also discuss why thyroid hormones may benefit performance, as well as safety.  I echo these sentiments, and further discussion is certainly required


Late addition:  

In posting on our Facebook page, the following occurred to me, so I'm sharing it below.  Related to the above, but to add a dimension from an old subject - females and testosterone.  It's about what we are born with, to some extent.  Some are just luckier than others!

Here's that post:

One final thought on the thyroid hormone issue, and I have to raise the ghosts of female/gender issues in sport. There are some "conditions", which are not really conditions, but rather normal variations in hormones that preclude certain individuals from succeeding in sport. For instance, a study by Cook et al showed clearly that female athletes with higher testosterone levels were elite, and those with lower levels were not (link in comments section below)

Such is life - you have it, or you don't. In some instances, those who have it become elite, those who do not, well, they become enthusiasts. Now, I am totally sympathetic to the fact that there are individuals who genuinely are affected by hormone imbalances. Hypothyroidism is real. As is hypogonadism in males, and a variety of other conditions.

But when it comes to elite sport, there's a certain element of luck in the genetic "lottery" that determines who becomes elite and who does not. I could, for instance, reasonably argue, that aspects of my physiology are inferior (compared to say, Usain Bolt's) and that the appropriate intervention by a doctor with some questionable ethical standards is all I need to join the ranks of the elite. In reality, it doesn't work this way, but I illustrate a point, which is to say that biological variation is part of what we celebrate when we crown an Olympic gold medalist!

And part of biological variation is the baseline physiology, as well as the adaptation to training, and the 'hardware' we take into an athletic career.  That is refined by training, but only when the training response is positive - that, in turn, is part of the physiology.  Some individuals cannot achieve the same success without medication and that to me puts this practice over the line of fairness.

Now, ideally, we will develop a way to clearly identify whether a person has developed hypothyroidism because of a genuine medical condition, or whether it is training related. As I've said in the article, when it's training related, I cannot see how the use of synthetic hormones can be justified. And given that this ideal situation is unlikely to exist, as much as I want to see a solution for all, I cannot. And thus, thyroid hormones should, in my opinion, be banned, unless it can be clearly shown that they have no performance benefit (which it can't because if they allow training in a fatigued individual, then the comparison must be with an athlete not training, and that's a clear performance benefit).