The Russian weightlifting team has been banned from the 2016 Olympics as a result of serious doping allegations but the use of performance-enhancing drugs at the Olympics is nothing new.
Chemistry plays a huge role on both sides of the performance-enhancing drug battle. On one side are officials and scientists, aiming to keep the competitions fair; on the other are underground or overseas chemists, creating new drugs to cheat the system.
Watch this quick clip to understand why so many professional athletes are tempted to cheat:
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