Doping represents the processes which allow improving artificially the performances. These processes are generally bio-chemical (pharmacological substances) but can be physical (blood transfusion, etc.). Unfortunately, with the evolution of scientific knowledge, the limits of doping are now difficult to define.
Doping is more used in the sports requiring intense physical efforts (strength, speed, endurance sports).
Doping has been used a lot during the last decades because of the mediatization of great sporting competitions. These competitions are subjected to huge constraints, on a financial level (Tour de France company, etc.) but also economic and political (Olympic Games, World Championships, etc.).
The recent scandals (athletics, cycling, etc.) are a proof there is no organism independent of sporting structures capable to do serious checks and repression. The sporting elite is then captive of a complex and ambiguous system in which the anti-doping fight has only for objective to "save appearances".
This "spectacle" sport does not have any common measurement with the "health" sport practised by the majority of the sportsmen.
Among processes capable of artificial performances improving, there are two categories corresponding to metabolisms (with or without oxygen).
Doping of anaerobic metabolisms
The objective is to increase artificially the muscular mass (speed or strength sports).
The increase of the quantity of "fast" fibers is fundamental for speed or strength needs. It can be made chemically with anabolics (nandrolone, testosterone, etc.) or physically (electro-stimulation, etc.).
Doping of the aerobic metabolism
The objective is to increase artificially the capacity to consume the oxygen (endurance sports).
The increase of the red corpuscles density allows favoring the transport of oxygen to the muscles. It can be made chemically (erythropoetin, darbepoetin, etc.) or physically (blood transfusion, stage in sub-oxygenated room, etc.).
The other forms of doping
Stimulants (ephedrine, amphetamine, cocaine, caffeine, etc.) act on the behaviour (attention improvement, tiredness reduction, etc.).
Narcotics (heroin, methadone, morphine, etc.) act on the pain.