Despite announcements that anti-doping plans were to be the “most stringent ever” for the 2014 Winter Olympics in Sochi, there are signs that doping options are still surfacing and are being sold to athletes.

According to an undercover investigation by German journalists, a particular Russian scientist has developed a new doping agent that can’t be detected with current anti-doping tests. The International Olympic Committee (IOC) had collaborated with the World Anti-Doping Agency (WADA) and Sochi 2014 officials in order to undergo 2,453 tests to ensure that Olympic athletes aren’t using steroids to enhance their performance. Recently, Russian biathlete Irini Starykh pulled out of the Games after she tested positive for steroid use.

Hajo Seppelt, a journalist for German broadcaster WDR, had tracked down the Russian scientist who was selling the new doping agent and was able to speak to him under the guise of an Olympic consultant. “I had a hidden camera with me and then the discussion began,” Seppelt told Motherboard. “First he was a little bit careful, but then he was very open and offered to arrange to give me a kind of test quantity to test if the substance is really the right one.” He had heard of the Russian scientist before, who had spoken at a conference rather openly about the substance’s doping qualities.

Seppelt agreed to pick up one milligram of the drug at a train station in Belarus. “With one milligram you can really dope at least one or two persons,” Seppelt told Motherboard. After acquiring the sample, Seppelt took it to the German Sports University in Cologne, where it was identified as Full Size MGF, which is similar to the “deer antler spray” being used by NFL players a while ago. Full Size MGF aids muscle growth and cannot be detected by current tests. It also hasn’t been officially tested on humans, only on animals; therefore its effects are widely unknown.

“I think we would be naïve if we thought that every athlete going to a major event, like the Olympic Games in Sochi, would be clean,” Director General of the World Anti-Doping Agency David Howman told the German broadcast.

Dr. Richard Budgett, the medical director of the IOC, meanwhile, emphasizes the toughness of the anti-doping plans that will be carried forth. “Well in Sochi we will have a more stringent and a more global testing program than ever before,” Budgett told EuroNews. “There are more tests, 14 percent more tests, but probably the most important change is the fact that they’re being targeted more intelligently than ever before.”

Doping use in sports or the Olympics has occurred since ancient times, when athletes would eat lizard meat in the hopes that it would give them a competitive edge. In 1967, the IOC banned the use of performance-enhancing drugs, and controlling doping use ultimately developed into a systematic-testing regimen that all Olympians must undergo. This typically involves urine and blood testing. Despite this, new drugs are constantly being developed at the same rate or faster than controlling methods. “It’s an uphill struggle,” Victoria Turk of Motherboard writes. “As tests evolve, so do performance-enhancing substances, so there’s always something new that testers don’t know about.”