Per WADA:

“Narcotics and cannabinoids
Narcotic analgesics decrease the painful sensations of serious injuries, potentially allowing athletes to continue training for competition after an injury. While some painkillers are allowed, including codeine.”


Those drugs make you mentally drowsy in addition
to relaxing muscles, slowing an athlete’s reaction and speed. They are
tranquilizers, which is why a person is not allowed to drive while on them.
No athlete in his/her right mind would take Xanax or Valium. They would
fall over in the blocks and possibly pass out.


Marijuana is not a tranquilizer. People are still able to be fully functional
mentally while getting the calm and relaxing benefits of the drug.