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From Microdosing to Designer Steroids: Uncovering how athletes cheat in the 21st century

When Lance Armstrong was stripped of his seven Tour de France titles and banned from professional cycling after he admitted in 2012 to using banned substances in his career, it sent shock-waves not just through the cycling fans but around the world.

Tour de France (1)

Maria Sharapova announced at a press conference in 2016 that she had tested positive for the recently-banned drug, Meldonium. Usually used to treat heart conditions, it had been added to the World Anti-Doping Agency’s (WADA) list of prohibited substances at the start of the year. She then served a 15-month ban from professional tennis.

In 2016, an independent report commissioned by WADA confirmed allegations that the Russian Olympic team had been involved in a state-sponsored doping programme that ran over the course of the 2014 Sochi Winter Olympic Games. A petition to prevent Russian athletes from competing on behalf of their country in the 2016 summer Olympics in Rio de Janeiro was rejected, and 287 athletes were allowed to participate for the Russian federation. 

These notorious cases of cheating show how world-class athletes are willing to risk it all on the most public of stages. How many broken records, gold medals, and superstar careers can partly be attributed to banned substances? We’ll never know, but labs such as King’s Forensics' Drug Control Centre - the only WADA accredited lab in the UK - are constantly pushing the envelope to keep pace with the latest doping trends.

Below, Dr Rodrigo Aguilera, Principal Analyst in the Drug Control Centre, details the methods competitors use to take performance enhancing drugs in the 21st century.

Androgenic - Anabolic Steroids

Anabolic Steroids, called more precisely Anabolic-Androgenic Steroids (AAS), are synthetic substances that mimic the effects of testosterone, the male sex hormone and in women, testosterone is produced in the ovaries and adrenal glands. This hormone helps the body with a number of different functions: normal testosterone levels in women help regulate mood and supports the health of female reproductive tissue and bones even though the concentration in females is very low.

Male Androgens are essential for the development and maintenance of specific reproductive tissues such as the testis, prostate, epididymis, seminal vesicle and penis, as well as for other characteristic male properties such as increased muscle strength, hair growth, etc. To maintain the androgen concentration at appropriate levels, the production rates of androgens in the body must be balanced against the individual rates of metabolic clearance and excretion. The action of androgens in target areas of the body is complicated and depends on the amount of steroids that can penetrate the tissue cells, the extent of metabolic activity (conversion) within the cells, the interactions at molecular level (with the receptor proteins) and finally the action of the androgen receptors at the genomic level (individual’s genetic makeup).

Anabolic Steroids are used to increase muscle size, strength and performance, and speed up the recovery stage

In sports, Anabolic Steroids are well known and are used to increase muscle size, strength and performance, and speed up the recovery stage. However, there are health risks associated with long-term use or excessive doses of AAS. These effects include harmful changes in cholesterol levels, acne, high blood pressure, liver damage, and dangerous changes in the structure of the left ventricle of the heart. These risks are further increased when athletes take steroids alongside other drugs, causing significantly more damage to their bodies. The effect of anabolic steroids on the heart can cause myocardial infarction (heart attack) and strokes. Conditions pertaining to hormonal imbalances such as gynecomastia (growth breast tissue) and testicular size reduction may also be caused by AAS.


The World Anti-Doping Agency (WADA) has long associated use of steroids as a means to boost performance, with a large portion of athletes believed to have used them. More recently, to avoid detection the administration of low amounts of endogenous hormones (AAS) - so-called micro-dosages – have been reported. This type of misuse represents a major challenge in sports testing analysis. Micro dosing may allow athletes to give themselves a perfectly timed boost before an important competition that cannot always be detected with current analytical methods.

Olympic games
Some Olympic athletes have been forced to return their medals after new technologies that were not available at the time have retrospectively uncovered banned substances

Most performance-enhancing steroids are synthetic (manufactured in a laboratory) variations on the male sex hormone testosterone. Testosterone-derived steroids are relatively inexpensive to buy, and because the body produces its own version naturally, they are generally harder to identify in a drug test.

The current approach for testing for steroids involves comparing a ratio of testosterone (T) and epitestosterone (E), both produced naturally in the body to determine if athletes have been doping. Epitestosterone is a testosterone isomer (that is it has the same formula but a different arrangement of atoms in the molecule and different properties to testosterone). Since the body produces roughly equal amounts of T and E naturally, most people have a ratio of one-to-one. Still, there is some natural variation, which is the reason WADA allows the testosterone-to-epitestosterone ratio to reach up to four-to-one for Olympic athletes. A laboratory result of >4:1 T/E ratio implies doping. Micro-dosing requires more frequent dosing delivered at just the right time. Some experts say athletes could even get a significant boost in muscle and strength by doping within the permitted ranges.

Designer Steroids

Novel AAS performance enhancers have appeared since the 1960s and continued to increase in the 2020s. These substances are synthesised from anabolic androgenic steroids and are presented as designer steroids. As other anabolic steroids, they are reported to be used by top athletes for doping purposes since they increase lean body mass, strength, aggressiveness, and lead to a shorter recovery time between workouts. The use of designer steroids e.g., Methylstenbolone often sold as nutritional supplements (Ultradrol, Methyl-Sten, or M-Sten), enables the athlete to improve their performance and increase muscle mass. However, an overconsumption can cause health issues such as testicular cancer, hypogonadism or neuro-psychic disorders, including domestic violence.

Therapeutic Use Exemption (TUE)

Asthma inhaler
Some otherwise banned substances can be used by athletes under a therapeutic use exemption

In contrast to the banned methods above, some anabolic steroids can be used by athletes under the therapeutic use exemption (TUE). This is also known as a temporary use exemption and has been available to athletes since 1991. This is an official medical document and authorised by any National Anti-Doping Agency (NADO) after a medical prescription. The document gives an athlete permission to take a medication listed on the World Anti-Doping Agency’s (WADA) Prohibited List.

These drugs would normally be prohibited because its use would be considered a performance enhancing drug. For instance, a TUE may be granted as an exemption for testosterone replacement therapy. This would require a medical examination to determine a legitimate reason for testosterone supplements. The average T / E ratio for a normal functioning male is a 1:1 ratio, but WADA allows up to a 4:1 ratio without testing positive for elevated testosterone. The ratio would be different for conditions such as hypogonadism, which can be monitored by the NADO for athletes requiring short term use of testosterone. Hypogonadism can be primarily caused by the testes or ovaries or could be a secondary problem with the pituitary or hypothalamus not functioning properly and would be diagnosed by a medical doctor. The testing laboratory would then be informed of the TUE for this athlete.

In this story

Rodrigo Aguilera

Rodrigo Aguilera

Principal Analyst in the Drug Control Centre

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