With doping back in the headlines after the news of Davide Rebellin and Stefan Schumacher's positives at the 2008 Olympic Games, we take a look at the substance they tested positive for - CERA.

CERA or Continuous Erythropoiesis Receptor Activator is a new form of EPO, created by the Swiss company Roche, that has been created to help dialysis patients or people with kidney problems.

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Founded in 1891, Cycling Weekly and its team of expert journalists brings cyclists in-depth reviews, extensive coverage of both professional and domestic racing, as well as fitness advice and 'brew a cuppa and put your feet up' features. Cycling Weekly serves its audience across a range of platforms, from good old-fashioned print to online journalism, and video.