A-Rod, Lance Armstrong, Jose Canseco, Rashard Lewis, Shawne Merriman. The list of superstar athletes accused of -- or admitting to -- taking performance-enhancing drugs is almost as impressive as the number of sports in which they compete. It's not just weightlifting, baseball and cycling. It's football, track and field, swimming, soccer and basketball. And it's not restricted to males -- or to professionals. Just ask former Olympic track star Marion Jones. Or the nine high school athletes in Texas caught using performance-enhancing drugs during the 2011-2012 academic year.
Once athletes like these would have found little in their medicine cabinets to help them get a leg up on the competition. Most would have turned to anabolic steroids, synthetic steroid hormones made to resemble testosterone. Chemicals in this special class of steroids, which include testosterone, androstenediol, androstenedione, nandrolone and stanozolol, increase muscle mass and strength, but tests can detect them easily.
In the 1980s and '90s, however, other doping alternatives started appearing on the scene. Now there are numerous performance-enhancing drugs, or PEDs, that aren't classified as steroids. Their effects are quite varied, and some only benefit certain athletes playing certain sports. All of which makes it extremely tricky for regulatory agencies like the International Cycling Union and the World Anti-Doping Agency to keep up -- and to keep drugs out of competing athletes.
On the next few pages, we'll present 10 of these non-steroid PEDs, looking at their modes of action and their side effects. Most entries will be individual drugs, but in a few cases, we'll consider a class of compounds and include some notable examples.
Let's kick everything off with EPO -- the drug that ushered in the modern era of doping.