BEIJING (AP) When the likes of Usain Bolt are openly expressing concern about the focus on doping ahead of the world championships, it signals a serious problem for the head of the international track and field federation.
Lamine Diack, the 82-year-old Senegalese official who is retiring after the world championships after 16 years as IAAF President, is hoping the swirling controversy will fade into the background when competition begins.
''As far as Usain Bolt is concerned. I know him well. He's in top form,'' Diack said of the world's fastest man. ''As from Saturday ... we'll talk about competition among the champions.''
Bolt reflected earlier Thursday on the doping cloud that has overshadowed the sport since German broadcaster ARD and The Sunday Times in Britain reported that 146 Olympic and world championship medals in middle- and long-distance races were won by athletes who have recorded suspicious tests.
''All I've been hearing about the past couple weeks is doping, doping, doping,'' Bolt said. ''It definitely is sad that it's in the forefront of the world championships, and it's not about the competition that's coming up.
''People say I need to win for the sport, but there are a lot of other athletes who are running clean, and they've been running clean their whole career.''
Diack thinks the scale has been blown out of proportion, saying the IAAF is ''convinced that 99 percent of our athletes are clean.''
Yet the focus was still very much on doping when Diack wrapped up the two-day IAAF Congress in Beijing, where two-time Olympic 1,500-meter champion Sebastian Coe was elected to replace him as president.
Diack said in his 39-year-old involvement the track and field federation had been at the forefront of the anti-doping campaign, including being the first sport to conduct out-of-competition testing and the first to ban an athlete for failing one, and being instrumental in the establishment of the World Anti-Doping Agency.
''I went through the whole evolution in terms of what happened in the struggle against doping,'' he said. ''I was there at the beginning - I'm here at the end.''
He rejected any comparisons with the embattled international cycling federation, which has been seriously tarnished by doping, and said the IAAF conducts 3,000 tests per year and 2,800 were negative.
''You focus on the bad news - the 200 positive tests,'' he told a news conference. ''We have no lesson to be taught by any other sport. We have done what we had to do. We started doing it before the others.
''This long-standing struggle we have been conducting and will continue to do - we cannot afford to have our performances being in doubt.''
As for the recent allegations, Diack said it was important for the independent commission investigating to have time to deliver its report, without undue pressure.
The IAAF last week denied it had tried to block publication of a 2011 study leaked to media in Germany and Britain, which asserted that blood doping was rampant. But it confirmed that 28 athletes had been caught in retests of their doping samples from the 2005 and 2007 world championships. The naming of those athletes has been delayed due to legalities.
In other items on the congress agenda, new term and age limits were passed for senior office holders: an IAAF president cannot serve more than three consecutive four-year terms, and IAAF Council candidates who reach the age of 70 during the year of an election congress cannot be elected or re-elected.
Diack again endorsed the 58-year-old Coe as the ideal person to move the organization forward.
''He loves this sport. He's very experienced. He'll do a great job - He knows a lot more about sport than I do or did myself as an Olympic champion and world-record holder,'' Diack said. ''When I leave I can say that I leave behind me a sport that is marvelous with beautiful performances throughout the 16 years that I've been leading this sport.''
AP National Writer Eddie Pells contributed to this report.
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