Mo Farah hits back at doping allegations after leaked document claims his coach gave him dangerous drugs to boost his performance

Great Britain's Olympic race champion, Mo Farah, 33, has hit back at doping allegations leveled against him after a leaked US Anti-Doping Agency report stolen by Russian hackers and passed to The Sunday Times, revealed his coach, Alberto Salazar issued 'potentially harmful' prescription medicines to him and other athletes to boost his performance. Farah, who called the allegations 'upsetting',