Performance enhancing substance was procured from Switzerland for athlete Mo Farah SWI swissinfo.ch Barry Fudge, physiologist and former UK Athletics head of endurance, says Mo Farah's victories were due to meticulous planning, hard work and determination as opposed to "some magical drug or illicit aid". Mo Farah Brought Joy and Late Closing Speed to Distance Running The New York Times Mo Farah interview from London Marathon exposed after changing account to doping officials Other Sport Express.co.uk Mo Farah, Alberto Salazar and L carnitine Q&A: everything we know