The use of cannabis by athletes has been banned by many sports commissions. However, some have relaxed their policies as societal attitudes towards its use have shifted. The prohibition "is one of the most controversial issues in anti-doping".[1]
There is no scientific consensus regarding the performance-enhancing effects of cannabis, with one 2018 paper reporting "there is no evidence for cannabis use as a performance-enhancing drug".[2][3] Other reasons cited for banning its use include an increased risk of injury in-competition and the view that users of cannabis are not good role models.[1]