When millions of dollars, a lifetime of fame and the promise of becoming immortalised in history books as one of the greatest are on the line, it is with little wonder that illegal doping to gain the slightest of edges becomes an enticing temptation to top athletes. Performance enhancement is not in the least bit novel. Ancient Roman chariot racers fed their racehorses mystery concoctions that pledged boosts in performance and masked injuries. The ancient Greek Olympians dabbled in performance enhancers by allegedly drinking herbal beverages to improve stamina and experimented freely with their diet to gain edge [1]. These stimulants were much less frowned upon in the ancient games and even deemed necessary to maintain competitiveness, but it was not until 1928 for the International Association of Athletic Federations (IAAF) to ban doping across the board. In addition to maintaining a fair standard of competition, many of these uncontrolled modern substances posed severe health risks to athletes who indulged [2].

Doping is primarily focused on androgenic agents such as anabolic steroids and blood doping via peptide hormones such as erythropoietin (EPO) and blood transfusions. Androsterone, an anabolic steroid, was first synthesised from urine in 1931, while testosterone synthesised from cholesterol was first commercially available in 1935 [3]. Both of these drugs enhanced strength. Androgenic agents are useful in medicine to stimulate growth, supplement low hormone levels, and act as a male contraceptive. The right dose of anabolic steroids also enhances muscle development. These fat-soluble hormones pass through the cell membrane to bind to the androgen receptors within the cytoplasm. The hormones then direct the cell nucleus to inhibit the stress hormone cortisol’s effects so that recovery time improves [4]. Athletes gain the advantage of training less to gain the same amount of muscle as their clean competitors.

EPO is a cytokine, a signaling molecule for red blood cell stems (hemocytoblasts) in the bone marrow. Its presence within the bloodstream stimulates red blood cell (RBC) production. While it is an effective treatment for anaemia, it has also had its fair share of doping scandals. A high RBC count equates to more oxygen being delivered to muscles and is particularly favourable for athletes involved in endurance sports, such as long-distance running, cycling, and swimming. Following this logic, some athletes choose to partake in high altitude training, where oxygen is less available due to lower pressure. This coerced hypoxic condition stimulates the kidneys to produce more EPO. Athletes who want to sustain high RBC levels can store their blood and re-inject it back into their bloodstreams at lower altitudes before an event, a process which is also known as autologous blood transfusion. When transfusion recipients are different, the process is called homologous blood transfusion [5].

The World Anti-Doping Agency (WADA) maintains sports integrity and fights against doping by implementing a biological passport that tests for certain performance-enhancing drugs. The passport retains logs of an athlete’s blood profile over time, allowing irregularities to be spotted which can signal doping. The exact methodology behind WADA’s dopant tests, however, is kept top secret in order to avoid dopers circumventing detection – but both sides are at a constant struggle to outmaneuver one another.

Numerous chemical laboratories have emerged to alter the chemical structure of steroids and peptides in an effort to evade detection with surprising success [6]. While approximately 1-2% of drug tests return positive, results concluded from surveys of athletes and coaches suggest that the true doping rate is between 14-39% [7]. With the exception of amphetamines, certain stimulants, and anabolic steroids, little research has been conducted on the efficacy of other dopants. The efficacy of EPO, for example, is based solely on 4 double-blind studies in which athletes increased their maximum oxygen intake and athletic performance only temporarily. It is also worth noting that the vast majority of WADA and the International Olympic Committee’s (IOC) contraband lists have not necessarily been proven as dopants. Many of these substances can be considered as placebos at best, or simply harmful to one’s health, at worst [6].

In this arms race between dopers and dopant screeners, gold medals are at stake as well as the integrity of the sport.

References

[1] Jenkins, S. Historical Timeline – History of Performance Enhancing Drugs in Sports (2013). Retrieved from http://sportsanddrugs.procon.org/view.timeline.php?timelineID=000017

[2] A Piece of Anti-Doping History: IAAF Handbook 1927 – 1928 (2006). Retrieved from http://www.iaaf.org/news/news/a-piece-of-anti-doping-history-iaaf-handbook

[3] History of Anabolic Steroids. Retrieved from https://www.steroidal.com/history-anabolic-steroids/

[4] Kickman, A. T., Pharmacology of anabolic steroids (2008). British Journal of Pharmacology. DOI: 10.1038/bpj.2008.

[5] Miller, G. Does Doping Work? (2008). Science. VOL 321 pp 627. Retrieved from http://sciencenetlinks.com/media/filer/2011/10/25/science_at_the_olympics.pdf

[6] Gibson, O. IAAF’s Lamine Diack: we are convinced 99% of athletes are clean. The Guardian. Retrieved from https://www.theguardian.com/sport/2015/aug/20/iaaf-lamine-diack-athletes-clean-drug-tests-sebastian-coe

[7] de Hon, O. Kuipers, H., van Bottenburg, M. Prevalence of doping use in elite sports: a review of numbers and methods (2015). Sports Med. NCBI. DOI: 10.1007/s40279-014-0247-x.