Performance-Enhancing Drugs

Performance enhancement is of major importance in competitive and elite sports. Among the many methods to enhance performance in sports, such as specialized training and diet regimes, some athletes seek resort to performance-enhancing drugs (PEDs). Following the drug-related death of British cyclist Tom Simpson during the 1967 Tour de France, a controversy erupted concerning the extent of drug use in sports and the health consequences of PEDs. Today, PEDs are broadly categorized into licit and illicit substances.

Since 1999, the World Anti-Doping Agency (WADA) has been regulating the use of illicit PEDs in sports. WADA annually issues an official list of prohibited PEDs and regulates drug testing and doping control procedures in collaboration with national anti-doping organizations (NADOs) across the world. The WADA list of prohibited substances distinguishes between substances that are banned at all times (both inside and outside competition), substances prohibited only incompetition, as well as substances prohibited only in particular sports.

The first class of substances (i.e., those that are banned at all times) includes mainly anabolicandrogenic steroids (AAS), such as human hormone testosterone and its synthetic or natural derivatives (e.g., androstenediol, androstenedione, DHEA, and 7-keto DHEA). Other anabolic agents in this category include clenbuterol, selective androgen receptor modulators (SARMs), peptide hormones, growth factors, and related substances (e.g., growth hormone, insulin-like growth factor-1 or IGF-1, and erythropoiesis-stimulating agents), beta-2 agonists, diuretics, and masking agents.

Prohibited in-competition substances include stimulants, narcotics, cannabinoids, and glucocorticosteroids. Additionally, some sporting associations prohibit the use of alcohol and beta-blockers. Some of the prohibited stimulants are considered legal if they are found in relatively low concentrations in the athlete’s urine during drug testing. Also, certain prohibited PEDs are allowed to be used for therapeutic reasons (Therapeutic Use Exemptions [TUEs]) and under medical supervision. This related mostly to narcotic analgesics and other drugs that can have a therapeutic value.

Health Effects

The use and abuse of illicit PEDs, such as amphetamines and anabolic steroids cause various psychological and physical health symptoms, such as irritability, aggressiveness, violent outbursts, depression, suicidal thoughts, acne, baldness, infertility and hypogonadism (in males using AAS), facial hair and deepening of the voice (in females using AAS), heart disease, and liver toxicity. Prolonged or excessive use of growth hormone has also been linked to the development of cancer, disfigurement of facial bones, and sudden death.

Epidemiology of Illicit Performance-Enhancing Drugs in Professional and Amateur Sports

There is a plethora of known cases of elite athletes using or abusing illegal PEDs. However, establishing reliable and accurate prevalence estimates of illicit PEDs in sports represents a difficult task for numerous reasons. First, the use of biomedical testing has proven problematic in relation to the high financial and administrative costs involved. Second, current testing procedures often fail to detect newly introduced, prohibited PEDs. Third, biomedical testing can only be applied to a small subsample of the total population of elite athletes, thus some athletes may be regular users of prohibited PEDs but escape testing. Finally, self-reports of drug use are also problematic, as elite athletes are reluctant to disclose drug use patterns. Therefore, while anecdotal evidence suggests that doping in elite sports may be more than 50%, official reports only support that the prevalence of illicit PEDs range from 5% to 10%. Clearly, there is still a great deal of work to be done concerning the epidemiology of illicit PEDs in sports.

Notably, several studies indicate that the use of illicit PEDs is not limited to competitive sports. Rather, illicit PEDs are also used in nonprofessional sports. Amateur athletes and adolescents engaged in recreational sports and leisure time physical activity (PA) self-report use of anabolic steroids and other banned substances. Some studies show that around 6% of adolescent athletes involved in organized sports in the United States have used AAS at least once in their lifetime. Other studies show that at least 10% of amateur, youth athletes, or leisure time exercisers attending fitness centers engage in illicit PED use. These findings are alarming because they show that the use of illicit PEDs is not a problem limited to the elite sports community. The reported prevalence rates among larger populations of leisure time exercisers and noncompetitive athletes indicate that illicit PED use is a growing and emerging public health risk. In fact, it can be argued that the health benefits of exercise and PA can be offset by the use of illicit PEDs, especially among chronic users and younger people.

Licit Performance-Enhancing Drugs

Nutritional supplements and licit performance-enhancement substances provide an alternative to illicit drug use in sports with no to minimal side effects on users. These products include a wide variety of substances, such as proteins, herbal-based products (e.g., Tribulus Terrestris), creatine, amino acids, stimulants (e.g., caffeine), multivitamins, and diet drugs. There is evidence that most of these substances yield benefits to physical health (e.g., the antioxidant properties of vitamins and herbal products support immune functioning), and increase athletic performance in diverse ways. Given their “legal” nature, nutritional supplements are widely used in both professional and amateur sports, across age groups, and even among people who engage in exercise for recreational purposes.

Nevertheless, there are several reasons to question the apparent legality and safety of licit performance-enhancement substances. First, nutritional and dietary supplements are not subject to strict testing and scrutiny by official regulatory authorities, such as the Food and Drug Administration (FDA). Consequently, many supplements may be contaminated with illegal PEDs, commonly anabolic steroids, or with other toxic substances, such as heavy metals. Such contamination can pose serious threats to consumer health and safety. Second, official reports reveal that elite athletes tend to abuse legal nutritional supplements by concurrently using up to 20 different substances, a practice known as “stacking.” The lack of proper regulation and labeling of the ingredients and the uncontrollable use of dietary supplements raise questions about the safety licit PEDs. Specifically, unknown interactions between substances, and liver toxicity resulting from prolonged use or abuse of PEDs, may prove health-threatening. Finally, several studies suggest that the systematic use of licit PEDs may act as a gateway to the use of illicit substances, especially among junior and early-career athletes. Thus, while legal PEDs can yield benefits to the user, there are major concerns surrounding safety of use. Also, the use of licit PEDs may enforce a mentality of drugassisted performance enhancement, and this may increase the risk to use illicit PEDs.

Determinants and Consequences of Performance-Enhancing Drug Use

The main reasons for PED use include weight management, improvement of physical stamina, building leaner muscle mass and burning fat, and/ or gaining other health benefits, such as a healthier skin or countering the effects of aging. In this respect, body image disturbances (e.g., body checking, investment in appearance) and social physique anxiety (SPA) can be related to the use of PEDs. Further, nutritional supplement users, particularly adolescents, are willing to engage in excessive use of supplements to achieve a better physique or improve performance, and tend to overlook the health risks involved in excessive use of nutritional supplements.

Prevention and Education

Drug control mainly applies to the use of illicit PEDs in sports, as the use of legal performance enhancement substances is still unregulated by official international sporting associations. The ATLAS (Adolescents Training and Learning to Avoid Steroids) and ATHENA (Athletes Targeting Healthy Exercise and Nutrition Alternatives) projects are based on education, awareness-raising, and training of adolescent athletes to increase abstinence from licit and illicit PEDs.

Conclusion

PEDs can be either licit or illicit, and they are used mainly to increase athletic performance and improve physical appearance. The use of illicit PEDs is related to adverse health problems and is banned from international sporting organizations. Athletes using such substances face legal sanctions and career termination. The potential negative outcomes of illicit PEDs may explain why the use of licit PEDs, typically known as nutritional or dietary supplements, has expanded considerably in both athletes and non-athletes. Licit PEDs may bring several health benefits to the user and assist performance enhancement. Nevertheless, careless and excessive use of nutritional supplements and lack of proper regulation of the supplements’ actual ingredients pose threats to the health of users. Most importantly, using nutritional supplements from an early age may reinforce polypharmacy trends and accordingly facilitate transition to illicit PEDs (the gateway hypothesis). Preventive efforts and educational approaches for illicit PED abstinence, as well as the safe use of licit PEDs are needed. Action should be also taken to regulate the ingredients and labeling of legal PEDs, so as to reduce the risk of contaminated products.

References:

Goulet, C., Valois, P., Buist, A., & Côté, M. (2010). Predictors of the use of performance-enhancing substances by young athletes. Clinical Journal of Sport Medicine, 20, 243–248.
Harmer, P. A. (2010). Anabolic-androgenic steroid use among young male and female athletes: Is the game to blame? British Journal of Sports Medicine, 44, 26–31.
Kafrouni, M. I., Anders, R. A., & Verma, S. (2007). Hepatotoxicity associated with dietary supplements containing anabolic steroids. Clinical Gastroenterology and Hepatology, 5, 809–812.
Laure, P., & Bisinger, C. (2007). Doping prevalence among preadolescent athletes: A 4-year follow-up. British Journal of Sports Medicine, 41, 660–663.
Petróczi, A., Taylor, G., & Naughton, D. P. (2011). Mission impossible? Regulatory and enforcement issues to ensure safety of dietary supplements. Food and Chemical Toxicology, 49, 393–402.
Simon, P., Striegel, H., Aust, F., Dietz, K., & Ulrich, R. (2006). Doping in fitness sports: Estimated number of unreported cases and individual probability of doping. Addiction, 101, 1640–1644.
Striegel, H., Simon, P., Frisch, S., Roecker, K., Dietz, K., Dickhuth, H., et al. (2006). Anabolic ergogenic substance users in fitness sports: A distinct group supported by the health care system. Drug and Alcohol Dependence, 81, 11–19.
Elliot, D. L., Goldberg, L., Moe, E. L., DeFrancesco, C. A., Durham, M. B., & McGinnis, W., et al. (2008). Long-term outcomes of the ATHENA (Athletes Targeting Healthy Exercise and Nutrition Alternatives) program for female high school athletes. Journal of Alcohol & Drug Education, 52, 73–92.