Last July, U.S. sprinter Tyson Gay held the fastest 100-meter time in the world. He appeared primed to give world record holder Usain Bolt a run for the crown at the 2013 world championships in Moscow the following month. But instead of discussing his acceleration phase, Gay struggled through sobs as he told reporters that he’d failed a drug test.

“I don’t have a sabotage story,” Gay said, after he’d been alerted to his positive test by the U.S. Anti-Doping Agency (USADA). “I don't have any lies. I don't have anything to say to make this seem like it was a mistake or it was on USADA's hands, someone playing games...I basically put my trust in someone and I was let down.”

Since then, the name of that someone, and the substance that triggered Gay’s positive test, have remained the subject of speculation among fans and other sprinters, who refer obliquely to “the Tyson situation.”

People with knowledge of USADA’s ongoing investigation have told ProPublica that the sprinter tested positive for a steroid or steroid precursor believed to have come from a cream given to him by Atlanta chiropractor and anti-aging specialist Clayton Gibson III.

The saga of the nation’s top sprinter likely done in by an obscure cream delivered by an anti-aging practitioner provides a view of the slipshod medical underworld of top-level sport, in which athletes risk their reputations in the enduring hunt for any competitive edge.

Time and again, premier athletes have turned to practitioners who employ novel or unproven methods. This can range from remedy peddlers with no credentials whatsoever — like the former male stripper who was plying NFL and professional golf stars with pseudo-mystical deer antler spray — to those who have invented and certified their own medical specialty, like the founder of “chiropractic neurology,” who was tasked with helping former National Hockey League MVP Sidney Crosby recover from concussions.

This hunt for any performance boost only intensifies as athletes reach their 30s, old age in explosive sports.

Says a former All-Pro NFL lineman who claims he was approached by Gibson, but declined to become his patient: “The culture now is: If you don’t have all this extra stuff, you’re not winning.”

Their claims notwithstanding, these unconventional practitioners often are unfamiliar with the intricacies of the drug tests athletes face, and the variations in standards from sport to sport. Some may not truly understand what is in the creams, potions and sprays they dole out to their clients.

Yet in elite athlete circles, their credentials can be less important than testimonials from fellow athletes, who look to what their competitors and peers are doing. Increasingly, this means turning to practitioners like Gibson who classify themselves as anti-aging specialists. Gibson’s client list has included football players such as Cincinnati Bengals defensive end Michael Johnson, New York Jets safety Ed Reed, Cleveland Browns running back Willis McGahee, and the late boxing champion Vernon Forrest.

The label on the cream Gay is believed to have used starkly says “Testosterone/DHEA Crème,” and lists testosterone and DHEA among its ingredients. DHEA is a hormone converted in the body to testosterone, and both DHEA and testosterone are banned for Olympic athletes. Two other listed ingredients, IGF-1 and somatropin — another name for human growth hormone — are also forbidden.

According to athletes and coaches who spoke with Gay about the cream, Gay insisted that Gibson told him that the product was “all natural” and that NFL clients had used it and passed drug tests. The label on the jar reads: “100% All Natural.”

David Howman, director general of the World Anti-Doping Agency, said it is “staggering” that an athlete today would use a supplement that so clearly advertised its banned ingredients.

“That’s where it falls into the level of negligence," he said.

Howman said his agency expected athletes to be hyper-cautious about supplements given the history of high-profile positive drug tests associated with them. Instead, he said, even world-class athletes “are relying more on people around them to be responsible and then, when they get let down, blaming those other people.”

Jamaica's Shelly-Ann Fraser-Pryce, Trinidad's Kelly-Ann Baptiste, and Allyson Felix of the United States compete in a 100-meter semifinal at the 2012 Summer Olympics. Baptiste failed a drug test in 2013 when, according to people with knowledge of her situation, she was consulting with chiropractor and anti-aging specialist Clayton Gibson III. (Paul Gilham/Getty Images)

Another world-class sprinter, Trinidadian Kelly-Ann Baptiste, who was in Gay’s training group, also failed a drug test last year. People with knowledge of her situation said she, too, was consulting Gibson and using the cream. In an interview, Baptiste, the bronze medalist in the 100 meters at the 2011 world championships, confirmed she had consulted with Gibson, but declined to comment further until her disciplinary process is concluded.

Anti-aging medicine is a controversial field that often advocates supplementing hormones that diminish naturally with age, including testosterone and DHEA.

Gay declined to comment pending the announcement of his discipline. Gibson, after a brief interview last year, declined to answer further questions.

Because of the secrecy of this world, and the ramifications for those who speak publicly about it, many of those interviewed for this story did so on the condition they not be named.

Gay’s path to Gibson began several years ago when the chiropractor gained the trust of several Ravens players. One of them was running back McGahee, now with the Browns. When McGahee began dating U.S. sprinter Marshevet Hooker, a 2011 world champion, Gibson had his entrée into the upper echelon of track.

McGahee declined to comment through his business manager. Hooker did not respond to phone messages or messages sent through her website and Facebook page.

Hooker’s coach, Jon Drummond, is one of the most prominent figures in U.S track. Drummond, a former Olympic gold medalist and world champion, was the Team USA relay coach at the London Olympics, where Gay and teammates won the silver medal. In 2012, Drummond was Gay’s coach.

In text messages and an interview, Drummond said he learned of Gibson from Hooker and discussed him with Gay, but “did not recommend that Tyson enter a relationship with him.” Drummond vehemently denied being aware of any creams that Gay was using that might contain banned substances.

Willis McGahee, #26, of the Cleveland Browns runs through Cincinnati Bengals defenders in a 2013 game. Gibson's client list has included former Pro Bowlers like McGahee. (John Grieshop/Getty Images)

People with knowledge of USADA’s investigation said the agency has been told that Drummond had carried the cream for Gay during a training camp in Monaco prior to the 2012 Olympics.

Drummond’s involvement is especially noteworthy because he chairs USA Track and Field’s Athletes Advisory Committee, which helps disseminate information — including about anti-doping procedures — from the sport’s governing body to athletes. Drummond did not respond to follow up texts and voice messages.

In a previous interview, Gibson said Drummond had referred Gay to him prior to the 2012 Olympic Trials. "We had [Gay's] blood tested and everything before the trials just as an evaluation and taking a history to learn about the patient," he said.

Gibson’s specialty, anti-aging, is not recognized by the American Medical Association, but does have its own educational requirements and certification program administered by the American Board of Anti-Aging Health Practitioners. The ABAAHP is not a member of the American Board of Medical Specialties, considered the gold standard organization for medical specialty boards and certification groups.

Gibson is a licensed chiropractor and completed a certification program in anti-aging medicine.

Other individuals who proclaim themselves anti-aging specialists lack any pertinent credentials. Anthony Bosch, the founder of the Miami clinic Biogenesis who recently told 60 Minutes that he injected Alex Rodriguez with testosterone and human growth hormone, billed himself as an anti-aging specialist with no license of any kind. (Bosch has said that he studied medicine in Belize).

One NFL agent, as well as the former All-Pro lineman, described Gibson as confident, smart and persuasive. “The fact that he is an African American with credentials who can offer to be a mentor is huge for recruiting players” to his practice, the player said.

Gibson’s foray into the world of elite athletes was bolstered by Georgia Tech football players, like the Bengals’ Johnson. Tennessee Titans defensive end Derrick Morgan, who went to Georgia Tech, said that Gibson’s office in Atlanta was close to campus and that his name spread through the team when he started working with Johnson.

Johnson’s mother said her son declined to comment. She would not discuss her son’s relationship with Gibson because he still sees the chiropractor.

By at least 2005, Gibson was courting the pros. According to NFL players who met Gibson that year, he was offering strength coaching, injury prevention services, training for the NFL’s pre-draft physical testing, known as the combine, as well as recommending supplements.

“He works with a lot of NFL guys,” said the former NFL All-Pro. “He convinces guys to use all this herbal stuff.” The former All-Pro and another professional athlete who worked with Gibson said he cited his Christian faith to reassure them, asserting that it would reflect poorly in the eyes of God if he gave someone a product that caused them to fail a drug test.

In 2008, after Forrest reclaimed the WBC light middleweight title, he thanked Gibson on television for helping with his nutrition program. In a testimonial for a 2010 book on acupuncture, Gibson is identified as, “personal physician to numerous elite, Olympic and Professional Athletes (NFL, NBA, MLB, USATF and NCAA).”

Safety Ed Reed playing for the Baltimore Ravens. Reed, now with the Jets, talked about working with Gibson in the off-season to ESPN. (Bob Rosato/Sports Illustrated)

Gibson was soon working with NFL luminaries. In an ESPN article, then-Ravens safety and eight-time All-Pro Ed Reed, said: “In the off-season, a few other guys and I work with Dr. Clayton Gibson and his anti-aging program in Miami every day for four hours. We do acupuncture, chiropractic work, foot detoxes.” (Foot detoxes have been widely criticized as pseudoscience by medical doctors.) Gibson’s Facebook page includes a picture of him leaving the Ravens’ hotel in New Orleans prior to last year’s Super Bowl.

In a locker room interview, Reed said that his work with Gibson “is a longer conversation.” He declined to respond to follow up questions and subsequent messages.

The cream that Gibson dispensed — and that Baptiste and Gay apparently used — is sold to chiropractors by West Coast Anti Aging, a company based in California and owned by Swiss chiropractor Erich Breitenmoser. West Coast Anti Aging’s Web site advertises a number of creams — which Breitenmoser said do everything from increase energy to burn fat, all while moisturizing.

In a series of online videos, Breitenmoser — clad in a black Adidas tank top, and lecturing in a professorial manner — touts the benefits of his creams. “Science has proven,” Breitenmoser says, that “the sooner you start using the cream and replenishing your hormones, the better health you’re going to have.”

Athletes aren’t alone in seeking hormone replacement. The number of men in their 40s who got prescriptions for testosterone more than quadrupled between 2001 and 2011, according to data published last year in a publication of the Journal of the American Medical Association.

In his pitches, Breitenmoser employs catchphrases such as “add life to years and years to life.” “I had one gentleman,” he says, “80 years old, hip problems” who started using the creams. “By only using them for 10 days he was able to go back, hike a mountain of almost 10,000 feet.”

Breitenmoser often adds that his elderly mother uses the creams and has never felt better, and that customers should make sure to slather on plenty. “People take three full [containers] twice a day,” he said in a phone interview. Hundreds of healthcare providers dispense the West Coast Anti Aging creams, he said.

Despite his enthusiasm, Breitenmoser was less certain about the ingredients in his products. The labels of the creams are unclear as to what precisely they contain, though substances banned in sports are advertised boldly.

The cream apparently used by Gay, for example, lists DHEA, along with “5% Testosterone in 10x, 30x and 100x potencies, Somatropin in 10x, 30x and 100x potencies,” but does not indicate the form or amount of testosterone or somatropin. The U.S. Food and Drug Administration would not comment on West Coast Anti Aging creams specifically, but a 2012 warning letter that the FDA sent to a group of homeopathic remedy manufacturers pointed specifically to “Testosterone 30x” as an example of illegal labeling.

Additionally, like many supplements, the cream — which lists “frequent erections” and “masculinity” as potential side effects — contains a medley of unproven ingredients. One is Tribulus terrestris, a very common ingredient in sports supplements because of claims that it boosts testosterone. It has, however, failed when tested in controlled studies, showing strength gains equal to or worse than a placebo.

When contacted, Breitenmoser said that the cream does contain DHEA, but does not actually include testosterone or somatropin, both of which are illegal without a prescription. “[The label listing of testosterone] is based on the homeopathic ingredients,” he said, “because during the manufacturing they refine it multiple times, and they use the percentage to explain that.”

Asked to explain further what that means, since testosterone is not a homeopathic ingredient, and what units or form of testosterone the label refers to, Breitenmoser said, “I don’t understand it either.” He said that he would have to ask his business partner, who formulates the product. “I have to find out why he put that on there,” Breitenmoser said. He didn’t return a subsequent message.

Even if, as Breitenmoser said, there is no testosterone in the cream, DHEA — which is metabolized to small amounts of the testosterone in the body — would have caused Gay to test positive. Moreover, DHEA is also metabolized into estrogen, which endocrinologists say could cause breast tissue growth in men and — testing aside — would not be advised as a good performance enhancer by sports doctors with an understanding of hormones.

DHEA is not banned in the NFL or Major League Baseball, so any of Gibson’s football and baseball patients who used the cream would not be sanctioned for DHEA. But anti-doping scientists said it can be used to mask other forms of doping in those sports. When mixed with testosterone, DHEA can confound drug testing, because it makes it difficult to tell whether an athlete took DHEA alone, or DHEA and testosterone together, the scientists said. Testosterone is banned in all professional sports.

Christiane Ayotte, director of the World Anti-Doping Agency accredited lab in Montreal, which analyzes MLB drug tests, said if an athlete was taking DHEA, “I could have a problem detecting whether the testosterone is coming from DHEA, or from a separate source.”

Lauryn Williams gets out of her sled after a training run for the U.S. bobsled team last week at the 2014 Winter Olympics in Sochi, Russia. In a blog post, Williams wrote about meeting Gibson, although she did not name him. (Natacha Pisarenko/AP Photo)

Olympic athletes who want to play it safe often shy away altogether from healthcare practitioners who deal in DHEA or testosterone, as did former 100-meter world champion Lauryn Williams.

In December, Williams — who retired from track and is currently on the U.S. bobsled team for the Olympics in Sochi — wrote a blog post in which she recounted meeting Gibson. Williams did not identify him, but people familiar with the matter confirmed that Williams met with Gibson and the blog post was about the meeting.

In the post, Williams wrote that a friend steered her to the chiropractor for help with a persistent hamstring injury. (According to these people, Reed was the friend.) “The picture he painted was that this guy was the ‘sports doctor of all sports doctors’,” Williams wrote.

Williams described how she met with the practitioner and questioned him about how his supplements are made, and that he couldn’t answer. “Wait you’re the maker and you can’t tell me how it is made??” she wrote. “He began to get uneasy, likely because he has serviced many elites, his reputation precedes him and I think I was the first to ever ask him any detailed questions.”

Williams wrote that she gave blood and saliva at the meeting, but grew nervous and consulted a doctor friend. The friend told her that because the practitioner classified himself as an anti-aging specialist, he would likely tell her that her hormone levels were off and should be corrected. In her post, Williams wrote that she was subsequently told that her testosterone levels were low, to which she said she responded: “I am a girl, I don’t need high testosterone.”

“He then told me that there is this ratio that I am well below and need to maximize,” Williams wrote. “This is when the alarms started sounding.” The most common anti-doping screen tests for the “T/E ratio,” or the ratio of testosterone to another hormone called epitestosterone. Most people have a ratio of about 1-to-1, and a test is only flagged as abnormal if the ratio exceeds 4-to-1. Thus, there is room for athletes to dope with testosterone and remain under the threshold.

Gay’s punishment has not yet been announced. A standard first-time ban for an Olympian who fails a drug test for a steroid or steroid precursor is two years, with possible reductions based on cooperation.

Howman, head of the World Anti-Doping Agency, said athletes should understand by now that hunting for an edge in a cream or potion will often end badly.

“Athletes say, ‘Well, Joe who I’m competing against is taking supplements so I’m going to too,’” he said. “That’s to me a Lance Armstrong approach, and it just doesn’t work.”

 For more on this subject, see David Epstein’s roundup of great #MuckReads on performance enhancing drugs in sports or listen to him on WBUR’s Here & Now discussing why athletes risk doping.