As long as there have been sports, there have been athletes trying to gain an edge at any cost.But in the modern world of designer drugs and a cutthroat media that leaves no stone unturned, no use or abuse of performance enhancing drugs goes unnoticed.
Many of the greatest moments in sports over the last 20 years have had the specter of drugs hanging over them, making the inevitable scandals as much a part of the game as box scores.
At the turn of the last century, the marathon was considered to be at the limits of human endurance, prompting what was perhaps the Olympics' first doping 'scandal.'
Thomas Hicks, a British-born American, was flagging late in the race, when his handler stepped in to give him brandy and an injection of strychnine -- a.k.a., rat poison.
The drug stimulated muscles, but only briefly, prompting his handler to give him another shot that was just enough to get him across the finish line, where he collapsed. (Another injection probably would have killed him.)
Hicks actually crossed the finish line second, but it was later determined that the man who won had ridden in a car over most of the course, which is probably the ultimate performance enhancer.
For nearly two decades, East German athletes (particularly on the women's side) were often accused of doping, as they dominated several Olympic disciplines, like swimming, speed skating, and track and field.
Though most accusations were never proven at the time, the reunification of Germany in the early 1990s revealed thousands of documents from the fallen regime, including those that showed a highly organised program of drug enhanced training for Olympic athletes.
The operation was supervised by the stasi security force, who provided drugs to hundreds of athletes, some as young as 10 years old, and often without their knowledge.
In a 1991 Sports Illustrated story, Alzado admitted to using anabolic steroids throughout his entire NFL career and that he believed abuse of the drugs had given him brain cancer.
One of the most fearsome hitters (and most famous, thanks to a post-football acting career) in NFL history, Alzado said that 90% of the athletes he knew were using steroids.
Doctors never conclusively linked the anabolic steroids to his cancer, but just two years later he was dead, sending a powerful warning to athletes and fans everywhere.
Perhaps the greatest drug scandal of the modern Olympics, Canadian Ben Johnson set a world record in the final of the 100-meters at the Seoul Games, but three days later was found to have failed a drug test and was stripped of his gold medal and the record.
Johnson later admitted that he'd used drugs in his training, but said it was only to keep up with other competitors.
Years later, it was revealed that Carl Lewis (who finished second and was given the gold and world record), had failed several drug tests in the run up to the Seoul Olympics, but was allowed to compete by USOC, who accepted his claims of 'inadvertent use.'
A hulking 6'5' and 300-plus-pounds, Mandarich was declared the 'best offensive line prospect ever' in a Sports Illustrated cover story that marveled at his ridiculous weightlifting feats.
He was also one of the most famous busts in NFL history, playing rarely and unremarkably before getting cut by the team that drafted him after just three seasons.
In 2008, Mandarich admitted that he used steroids throughout college and even faked a drug test before the 1988 Rose Bowl -- but said he didn't use them in the NFL, which would account for his dramatic pro drop-off.
In 2002, a year after retiring from baseball, the former Astros third baseman admitted that he used steroids for most of his career, including 1996, when he won the Most Valuable Player Award.
Caminiti also had problems with alcohol and cocaine, and two years after that story was published he died of a heart attack, brought on by extensive drug use.
Snowboarding was officially added to the Olympic Games in 1998 at Nagano, Japan, and the first gold medal to be awarded went to Canadian Ross Rebagliati for the Giant Slalom.
Rebagliati immediately failed a drug test because he had used marijuana before the competition and was disqualified.
However, even though THC was on the banned substances list, it was not officially considered a performance enhancing drug, so he was allowed to keep his medal.
Just days before the start of the 1998 Tour, a member of the Festina cycling team was arrested by customs officials who discovered anabolic steroids and other doping products in his luggage.
The subsequent investigation resulted in every member of the team being arrested and kicked out of the race, including one of the favourites, Richard Virenque, who had finished third two years earlier.
The case also embroiled several other teams and their coaches and threw a spotlight on the widespread and highly systematic use of doping in the world of cycling.
Every Tour de France winner since that race has been accused or implicated in the use of performance enhancing drugs.
In 2003, federal agents began an investigation of the San Francisco-area laboratory accused of providing illegal drugs to professional athletes.
The BALCO case led to a best-selling book, a special investigation by Major League Baseball, years of court trials, congressional hearings, leaks, accusations, apologies, and criminal convictions of at least four pro athletes who were clients of the lab, including Barry Bonds and sprinter Marion Jones.
Perhaps the biggest athlete casualty, Jones was forced to admit that she took steroids in her training, spent two years in jail for perjury and check fraud, and had to surrender the five medals she won at the 2000 Summer Olympics.
Amid growing concerns about steroid use in baseball -- and the record book assault by Barry Bonds -- MLB begins a 'pilot' drug testing program, that will randomly test hundreds of players to determine if a more stringent drug enforcement policy would need to be enacted.
Although the tests were supposed to be anonymous and those who failed would not be punished, the list of 104 failed tests was seized by government investigators and the results linked to the names of players.
Though no punishments were ever handed out, years later several prominent players -- including Manny Ramirez, Alex Rodriguez, Sammy Sosa, and David Ortiz -- have been identified by the media as having failed those drug tests in 2003.
Part biography, part tell-all, Canseco's controversial book not only contained admissions of steroid use during his baseball playing days, but named several other prominent players who he claimed were also using steroids.
In some of the cases, Canseco said he personally injected his teammates with illegal steroids.
Though ridiculed as self-serving and sensational, the book turned out to be quite prescient, as many of the claims would later be corroborated by other investigations.
On March 17, 2005, the House Government Reform Committee called several MLB players to testify about the use of PEDs in their sport.
Among those present were Canseco, McGwire, Sammy Sosa and Rafael Palmeiro. Sosa and Palmeiro denied using steroids.
Later that year, Palmeiro was suspended for failing a drug test. In 2009, Sosa was named as one of the players who failed the 2003 drug tests.
McGwire refused to answer Congress' questions that day, but in 2010 he finally admitted that he used drugs as a player ... but did not believe they affected his performance.
The American cyclist finally rose to the top of the bike world, but a failed drug test during the 2006 Tour led officials to strip Landis of his title.
After a two-year suspension and lengthy appeals effectively ended his career, Landis admitted in 2010 that he did use performance enhancing drugs and that former teammate and 7-time Tour de France Lance Armstrong used blood doping drugs as well.
Landis' accusations have led to an ongoing investigation of Armstrong, who has always maintained that he has never used any illegal substances to win. In 2011, another former teammate, Tyler Hamilton, corroborated many of Landis' claims.
During spring training in 2009, Alex Rodriguez admitted that he had used performance enhancing drugs while a member of the Texas Rangers.
The admission was prompted by a Sports Illustrated story that claimed A-Rod had failed his MLB drug test in 2003. The test was meant to be anonymous (and not subject to punishment by MLB), but became public after investigators seized the results of the tests as part of the BALCO investigation.
In 2003, Bonds testified in front of the BALCO grand jury and denied that he ever knowingly used PEDs.
Eight years later, after numerous appeals and legal challenges, baseball's all-time home run leader was convicted of obstruction of justice for giving misleading answers during his testimony, but was found not guilty on charges of perjury.
The appeals are still ongoing.
In 2009, Ramirez was suspended 50 games after failing a drug test, becoming the most famous victim of baseball's recently installed drug testing regime.
Just days into the 2011 season, Ramirez failed a second-drug test raising the possibility of a 100-game suspension. Rather than appeal or serve the ban, he retired.
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