Cannabinoids are natural substances extracted from Indian hemp (Cannabis sativa) as well as their synthetic analogues (similar artificially produced substances). The principal active substance is tetrahydrocannabinol (THC).
Cannabinoids have a relaxing and mildly euphoriant effect. Cannabis is rarely consumed to enhance performance, but its abuse outside of sport leads to many positive doping samples.
Cannabis is prohibited in competition in all sports. On the one hand, because its relaxing and mildly disinhibiting effect can indirectly influence performance, and on the other hand, because it can be a safety risk.
Effect of cannabinoids
Cannabinoids act predominantly on cannabinoid receptors type 1. Cannabinoid receptors type 1 (CB1) are located particularly on the nerve cells of the central nervous system. The brain regions in which the CB1 receptors are mainly located play an important role for memory (hippocampus and cerebellum) as well as motor control (basal ganglia and cerebellum).
Cannabinoids reduce the excitability of the brain and activate its dopaminergic reward system, i.e. they stimulate the production of the messenger substance dopamine which induces pleasant feelings of self-affirmation and well-being (being high).
Cannabinoids act predominantly on the brain.
By docking onto opioid receptors on the pre-synaptic knobs of the nerve cells, they modulate ion channels and intracellular signal paths and thus reduce the transmitter release at the synapse. By this mechanism, they reduce the excitability of the brain. The result is a relaxing, pain-relieving and frequently also demotivating effect. The dopaminergic reward system of the brain is activated.
⬆ Pain relief
Side effects and consequences of cannabinoid abuse
Cannabinoids act predominantly on the brain and can have a wide range of adverse effects. In the short term, they reduce motivation for physical performance and impair perception and short-term memory. At high doses, psychotic states, restlessness, anxiety, panic reactions and disorientation can occur. Long-term abuse can lead to attention deficit disorder, memory loss and reduced learning ability as well as changes in personality structure and, last but not least, psychological dependence.
Cannabinoids can reduce pre-competition tenseness and anxiety and increase the willingness to take risks, which may be performance-enhancing in some circumstances. In most sports, however, the undesired performance-decreasing effects predominate, e.g. delayed reactivity, impaired coordination and reduced motivation for physical performance. Cannabinoid abuse occurs mostly outside of, and unrelated to, the sport context. As a result, doping cases have emerged in all kinds of sports. They are particularly frequent in team sports (professional to amateur leagues).