Elite tennis player Maria Sharapova’s fall out over banned substance Meldonium has been all over the news the past couple of weeks. This drug was added to the list of prohibited substances only in January 2016 and as of the 15th of March 2016 it has already been reported in 100 athletes.
Meldonium is used in Eastern Europe to treat angina and heart stroke: severe cardiovascular problems related to lack of blood supply to vital muscles. It is unlikely that any of those elite athletes actually suffered from those diseases. Most of them were taking the drug with the aim of enhancing
their performance- and they were getting away with it.
Ironically, the performance enhancing properties of this drug- and of many of the other doping substances- have never been conclusively proved. And yet, doping is commonplace in today’s sports world.
In order to lead a global response to this problem, The world anti-doping agency (WADA) was founded in 1999. It annually produces the world anti-doping code, a list of prohibited substances and methods that sportspersons are not allowed to take or use.
The code is divided in three main sections: (1)Substances and methods prohibited in and out of competition, (2) substances and methods prohibited only in competition and (3) Substances and methods prohibited only in certain sports.
The third group comprises substances which are especially dangerous or relevant for certain sports, like alcohol in motorcycling. The second group includes drugs which alter the mindset during the competition, retarding pain and exhaustion. Some examples are cocaine, amphetamines, strong narcotics (e.g. derivatives of morphine) and cannabis.
The first group is the most complex one from a physiological point of view. It gathers drugs and methods aimed to change the performance of the body in the long term. The exposure is longer, which increases the odds of suffering long term or permanent adverse effects.
But what are the sought after effects? Mainly two: (1) accumulating muscle mass and (2) increasing the oxygen supply.
1- Increasing muscle mass
Anabolic steroids: substances from the family of steroids which enhance the accumulation of muscle tissue. The best representative of this group is testosterone, the “male hormone”. Structurally it is a steroid, and so it is chemically similar to other steroids like cholesterol, progesterone (female hormone) and aldosterone and cortisol (regulators of inflammation and liquid balance in the body).
Testosterone is produced by men in great quantities and it is responsible for “masculinizing effects” (beard, growth of the penis, etc) and it also has muscle building effects or “anabolic effects”.
The WADA list includes testosterone and up to 90 other steroids, natural or synthetic, which can exert a similar function or which can be converted into testosterone once inside the body. Anti-feminine hormones belong to this group as well, as they alter the hormonal balance in favor of testosterone.
Steroid abuse causes a huge amount of stress to the body. Interference with the sexual hormone balance reduces production of testosterone in men, resulting in shrinkage of sexual organs, infertility and weakened sexual function. In women, these substances end up causing, amongst other problems, breast shrinkage, infertility, enlargement of clitoris and baldness. Interference with the non-sexual hormones (like aldosterone and cortisol) have even more severe effects including increased risk of heart and vascular disease.
Other hormones are also prohibited because they stimulate the production of testosterone. Some examples are Gonadotrophin, luteinizing Hormone and Corticotrophins (ACTH). They also interfere with other hormones, causing a myriad of adverse effects. Importantly, it has not been proved that they enhance performance at all!
Growth hormone deserves a paragraph for itself. It is used in the clinic to treat dwarfism and other hormonal syndromes. It has been claimed to have anabolic effects. And while there is no proof of its performance enhancing properties, its abuse is related to some horrifying adverse events like gigantism, infertility, pain and deformation in the joints, diabetes and cardiovascular disease.
2- Increasing the oxygen supply to those muscles
Let’s have a look now at this second group of prohibited substances. The same way that a fire needs oxygen to burn efficiently and generate heat, the muscle needs oxygen to efficiently burn nutrients. When the oxygen supply is insufficient, the muscle can still partially burn the nutrients, but it is a less efficient process which results in undesirable by-products like lactic acid, which accumulates and causes sore muscles. These different oxidation process are called “aerobic” and “anaerobic” respectively.
Red blood cells are responsible for transporting oxygen from the lungs to the muscles. An increase in red blood cells results in increased performance and endurance. Therefore, any method or drug aimed to increase of red blood cells is prohibited. For example, erythropoietin (EPO), a hormone responsible for red blood cells production. Oxygen carriers and substances which result in increased EPO (like HIF stabilisers) are also prohibited. Meldonium belongs to this group. The adverse effects of these substances include blood vessel clogging and stroke. Its potential carcinogen effect is being explored.
Another way of increasing the oxygen supply could be expanding the airways. That is the mechanism of action of beta-2 agonists like formoterol and salbutamol. These are used to treat asthma and other severe respiratory problems, and they have not been proved to increase performance in athletes- unless they are asthmatic. They are allowed if needed and only if inhaled, but tablets and injections are prohibited. Adverse effects include sweating, hyperventilation and anxiety.
The list goes on. Diuretics to lose weight quickly and enter different weight categories or eliminate other prohibited substances from the body; insulin to stimulate the muscle uptake of nutrients. Blood transfusions to hide prohibited substances or to increase the concentration of red blood cells or growth hormones… you name it!
I have only discussed the substances classified as “prohibited”, but that is definitely a blurred line. Other practices are allowed and common place- yet they are unhealthy: hyperproteic or hypocaloric diets, for example, also put the athlete at risk.
It is a mistake to think that doping only happens in the context of elite sports. Performance enhancer intake and extreme diets are common place amongst amateur athletes, who are less controlled and more prone to suffer the consequences.
The take home message is that sportspersons are often victims of unethical non-scientific practices which expose healthy subjects to powerful drugs at doses, combinations and conditions frequently not tested in clinical trials, entailing enormous risks and frequently non-proved benefits. Education and social awareness are the only way to help athletes resist the pressure to take these shortcuts.