Sochi - Athletes who dope were on Saturday warned at the Sochi Games that if they escape detection now they still may be caught later.
The International Olympic Committee (IOC) medical commission chairperson Arne Ljungqvist said samples could now be tested within a 10-year period as a result of new anti-doping regulations.
It will allow possible new methods of detection to be applied to samples taken at the Games, he said.
"The message to the athletes (is) that if you cheat, if you take drugs, if we don't find you now we may find you later and we will certainly find you sooner or later. That is an important deterrent message," he said.
So far there have been no positive doping tests at the Games after 1 799 of 2 453 controls.
The World Anti-Doping Agency WADA will have a new statute from 2015 allowing for samples to be preserved for 10 years instead of eight.
"We will exercise that as from now, so these samples that were being collected here will be preserved for 10 more years with a possibility to test them again with new techniques or for substances that we may not have been aware of," said Ljungqvist.
Further testing of samples taken from the Turin 2006 Games have also been completed. The IOC is expected to make the findings known after the Sochi Games.
Ljungqvist said there had been delays "for various technical reasons" but "once we have the full information and full evaluation done from those retesting procedures we will give an official announcement."
The freezing of doping samples was introduced for the 2004 summer Games in Athens. As a result of the procedure, there were several positive results from the 2009 Beijing Games.
There was one positive doping test from the 2010 Winter Games in Vancouver and seven each from the 2002 Games in Salt Lake City and 2006 Turin Games.