Summary: With research suggesting that humans could retain the benefit of steroids for decades we ask if Justin Gatlin's dominance in sprinting after two drug bans is casting a long shadow over the sport. Mark Chapman is joined by Olympic Gold Medallist Darren Campbell, BBC Athletics Correspondent Mike Costello and BBC Chief Sports Writer Tom Fordyce. We'll hear from Justin Gatlin's manager, former British hurdles world champion Dai Greene, and the Scientist behind the study as well as the World Anti Doping Agency.
