Jan. 18, 2013 -- In an interview with Oprah Winfrey, disgraced cyclist Lance Armstrong finally admitted to using banned, performance-enhancing substances in his efforts to win seven Tour de France titles. He went on to describe the level of doping in cycling, claiming there were "five guys" while he was riding who weren't cheating.

Armstrong's description of the prevalence of doping in cycling is in line with reporting on the culture of cheating within the sport. But cycling isn't the only sport that gets a bad rap for athletes using more than their natural talent to get ahead.

Baseball, football, boxing, track and field, and many other sports have had their fair share of disgraced athletes, though none have admittedly fallen from grace quite as dramatically as Armstrong.

Given how prevalant cheating is these days, it can be difficult to sort out the range of substances that athletes abuse to get ahead. And although different sporting disciplines have their own regulations in terms of regulations and controls, the same drugs seem to keep coming back.

Erythropoietin (EPO) is a banned substance that didn't get a lot of attention before the Armstrong scandal. EPO is naturally produced in the body and stimulates the production of red blood cells in bone marrow.

Although it's typically used in patients who are severely anemic, athletes competing in endurance events like cycling can receive injections to boost their performance. The elevated levels of red blood cells deliver more oxygen to the muscles, which allows them to do more work.

EPO is one of the substances Armstrong admitted to using.

Human-growth hormone, among the most popular steroid used by cheating professional athletes, including Armstrong, does exactly what its name would imply: promotes muscle growth. The steroid has the added benefit of strengthening bones and tendons, which is why its often administered to patients coping with range of conditions from children with growth hormone deficieny to adults dealing with muscle atrophy as a result of aging or disease.

Profesional athletes use it to boost their strength and muscle mass. Baseball players, including Jason Giambi (pictured here), who later apologized in a press conference for steroid use, were among the most frequent users of HGH.

Using Tetrahydrogestrinone, also known as "THG" or "the Clear," didn't make Barry Bonds the most hated player in baseball of his time. He managed to do that all by himself.

It did, however, help to fuel a wildly successful baseball career that included 14 All Star appearances, four MVP titles and several home run records. By lying to a grand jury about his use, he also winded up before a judge and almost in jail.

THG was a synthetic steroid designed by Bay Area Laboratory Co-Operative (BALCO), the California-based company that provided a number of athletes with a once undetectable performance-enhancing drug.

Human Chorionic Gonadotropin, or "HCG," was another steroid that proved popular among baseball players, most notably Jose Canseco, who was caught by authorities trying to smuggle the hormone across the border from Mexico.

HCG isn't used by itself, but rather after a steroid cycle. Steroids can shut down the bodies natural testosterone production, and HCG is a drug that helps men produce testosterone and sperm. HCG is also used medically to help women get pregnant.

A steroid popular among bodybuilders (almost guaranteeing athletes will abuse it as well), Winstrol is a steroid much like HCG in that athletes typically don't use it by itself.

Winstrol is another hormone athletes might take when off-cycle from another steroid. The purpose of the drug among athletes and bodybuilders isn't so much to build muscle, but retain it after a "bulking cycle" and cut fat.

Ben Johnson, the Canadian sprinter who beat Carl Lewis at the 1988 Olympics, might be the most famous user of Winstrol, and had his gold medal stripped as a result of testing positive for the compound. Johnson never denied using, and alleged that other athletes in the competition had all been cheating with performance-enhacing drugs.

Although banned today, amphetamines, also known as speed, were once common in sports, ranging from baseball and football to gymnastics and wrestling.

These potentially addictive performance enhancers give a boost with heightened alertness and increased confidence, and can reduce perception of pain. These drugs also comes with a wide range of negative potential side effects from increased blood pressure to hallucinations to heart attack.

Last November, Balitmore Orioles shortstop Ryan Adams was suspended after he tested positive for amphetamines.

Ephedrine is a stimulant used by athletes to give themselves an energy boost.

Not only is ephedrine a banned substance by multiple sporting organizations, but it's also illegal to sell the herb from which it is derived, ephedra. Ephedra is potentially dangerous and has been implicated in the deaths of athletes both amateur and professional.

One of the earliest famous cases of ephedrine use in professional sports was Diego Maradona, who was booted from the 1994 World Cup after he tested positive for it. He later claimed that the compound was present in a sports drink and he had only ingested the drug inadvertently.