JOHANNESBURG (AP) -- Serious doping cheats will be banned for four years from 2015, ensuring they miss at least one Olympics.
The doubling of bans from two years to four was one of the proposals adopted by the World Anti-Doping Agency and added to the World Anti-Doping Code on Friday, the final day of the World Conference on Doping in Sport in South Africa.
Also added to the revised code were stronger powers for anti-doping authorities to punish coaches and trainers who help athletes dope, and more emphasis on investigations away from drug tests to catch cheats. The code will come into effect on Jan. 1, 2015, in time for the 2016 Rio Olympics.
Another key change to international anti-doping rules is WADA's ability to tell sports which illegal substances they should be testing for.
''The executive committee unanimously endorsed and agreed to approve the code and the standards,'' WADA President John Fahey told delegates. ''This is a good day for sport.''
Away from the main business of adopting a new code, WADA also made progress on two key behind-the-scenes issues at the conference.
WADA and the International Cycling Union announced an agreement to set up an independent commission of inquiry into the sport's drug-stained past, and a report from an audit of Jamaica's troubled drug-testing program has now made recommendations to authorities on the Caribbean island.
Sports or countries deemed not compliant with WADA rules can be thrown out of the Olympics, and this week's conference was attended by International Olympic Committee President Thomas Bach.
However, problems over allegations of widespread doping in distance running powerhouse Kenya remain despite reports that the East African country has finally set up an investigation to probe the allegations made more than a year ago. WADA has not been officially informed of any Kenyan inquiry and has openly said it is ''frustrated'' with authorities there.
In the new code, the move to four-year bans as standard for intentional doping was seen as the most obvious deterrent, although there are still provisions in the new code for ''flexibility'' if an athlete takes a banned substance unintentionally or an athlete tests positive for a social drug like marijuana.
While the tougher four-year bans had widespread approval, the focus on intelligence gathering and investigations away from testing of urine and blood samples may be a more important new tool.
Many of the most significant recent breakthroughs to catch high-profile dopers - including disgraced American cyclist Lance Armstrong, the BALCO scandal in the United States and Spain's Operation Puerto - have come through investigations and not analytical tests.
Armstrong was banned for life in 2012 and stripped of his seven Tour de France titles after an extensive investigation by the United States Anti-Doping Agency. Armstrong was implicated and punished despite never failing a doping test.
WADA said Friday it was ''emphasizing the need to encourage more investigations into doping practices as a complement to efficient testing programs.''
WADA also strengthened its powers to punish ''athlete support personnel,'' the trainers, coaches and officials that assist in doping. Previously, coaches and officials were not subject to the same anti-doping rules as athletes.
The amendment concerning ''smart menus'' allows WADA to tell sports federations to test for substances ''most likely to be abused'' by athletes in their sports.
WADA has been working on the changes to its international anti-doping rules - which will be the first update since 2009 - in a two-year process involving athletes, sports federations, anti-doping bodies and governments. There were more than 2,000 proposed clause changes for the new code, 145 meetings with stakeholders and 18 code drafting sessions, WADA said.
''We must turn those words, those intentions, into action,'' Fahey said in his farewell address.
WADA will elect a new leader on Friday to succeed Fahey. Britain's Craig Reedie, an IOC vice president, is the only candidate to take over as president. He is set to take office on Jan. 1.
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