Performance-enhancing substances, also known as performance-enhancing drugs (PED), are substances that are used to improve any form of activity performance in humans. A well-known example involves doping in sport, where banned physical performance–enhancing drugs are used by athletes and bodybuilders. Athletic performance-enhancing substances are sometimes referred to as ergogenic aids. Cognitive performance-enhancing drugs, commonly called nootropics, are sometimes used by students to improve academic performance. Performance-enhancing substances are also used by military personnel to enhance combat performance.
The use of performance-enhancing drugs spans the categories of legitimate use and substance abuse.
The classifications of substances as performance-enhancing substances are not entirely clear-cut and objective. As in other types of categorization, certain prototype performance enhancers are universally classified as such (like anabolic steroids), whereas other substances (like vitamins and protein supplements) are virtually never classified as performance enhancers despite their effects on performance. As is usual with categorization, there are borderline cases; caffeine, for example, is considered a performance enhancer by some but not others.
The phrase has been used to refer to several distinct classes of drugs:
Anabolic drugs build up muscle; examples include steroids hormones, most notably human growth hormone, as well as some of their prodrugs, selective androgen receptor modulators and beta-2 agonists.
Stimulants improve focus and alertness. Low (therapeutic) doses of dopaminergic stimulants (e.g., reuptake inhibitors and releasing agents) also promote cognitive and athletic performance, as nootropics and ergogenic aids respectively, by improving muscle strength and endurance while decreasing reaction time and fatigue; some examples of athletic performance-enhancing stimulants are caffeine, ephedrine, methylphenidate, and amphetamine.
Ergogenic aids, or athletic performance-enhancing substances, include a number of drugs with various effects on physical performance. Drugs such as amphetamine and methylphenidate increase power output at constant levels of perceived exertion and delay the onset of fatigue, among other athletic-performance enhancing effects; bupropion also increases power output at constant levels of perceived exertion, but only during short term use. Creatine, a nutritional supplement that is commonly used by athletes, increases high-intensity exercise capacity.
Human biomolecules – creatine and β-hydroxy β-methylbutyrate are naturally occurring compounds in humans that have well-established ergogenic effects and effects on body composition when supplemented.
Adaptogens are plants that support health through nonspecific effects, neutralize various environmental and physical stressors while being relatively safe and free of side effects. As of 2008, the position of the European Medicines Agency was that "The principle of an adaptogenic action needs further clarification and studies in the pre-clinical and clinical area. As such, the term is not accepted in pharmacological and clinical terminology that is commonly used in the EU."
Nootropics, or "cognition enhancers", benefit overall cognition by improving memory (e.g., increasing working memory capacity or updating) or other aspects of cognitive control (e.g., inhibitory control, attentional control, attention span, etc.).
Painkillers allow performance beyond the usual pain threshold. Some painkillers raise blood pressure, increasing oxygen supply to muscle cells. Painkillers used by athletes range from common over-the-counter medicines such as NSAIDs (such as ibuprofen) to powerful prescription narcotics.
Sedatives and anxiolytics are sometimes used in sports like archery which require steady hands and accurate aim, and also to overcome excessive nervousness or discomfort. Diazepam and propranolol are common examples; ethanol and cannabis are also used occasionally.
Blood boosters (blood doping agents) increase the oxygen-carrying capacity of blood beyond the individual's natural capacity. They are used in endurance sports like long-distance running, cycling, and Nordic skiing. Recombinant human erythropoietin (rhEPO) is one of the most widely known drugs in this class.
Gene doping agents are a relatively recently described class of athletic performance-enhancing substances. These drug therapies, which involve viral vector-mediated gene transfer of a human protein, are not known to currently be in use as of April 2015.
In sports, the phrase performance-enhancing drugs is popularly used in reference to anabolic steroids or their precursors (hence the colloquial term "steroids"); anti-doping organizations apply the term broadly. There are agencies such as WADA and USADA that try to prevent athletes from using these drugs by performing drug tests. WADA was founded on November 10, 1999 by Dick Pound. The World Anti-doping Agency focuses on establishing and enforcing rules and codes of all sports around the world. Their goal is to make all sports played fairly between all athletes in a doping free organization with the power to prevent athletes from using any form of performance-enhancing drugs. USADA started October 1, 2000 as non-profit and was composed of nine members. Five of which were former Olympic athletes with the other four elected from independent companies. This is the United States Anti-doping Agency and have the ability to test athletes across the nation. Steroids and performance-enhancing drugs are used across all sports organizations around the world.
