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David Rudisha conceded doping has been a "big problem" in his native Kenya, but he is hopeful for the future.
The 27-year-old made history at Rio 2016 as he defended his 800 metres title – the first man to do so since 1964.
Afterwards he was questioned on Kenya's doping issues, with the country's president Uhuru Kenyatta having singed anti-doping legislation in June.
Rudisha said: "The issues about doping have been a big problem.
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"There have been a lot of allegations going around, but when the president signed a deal a few months ago that was a big boost and will help reduce the vices.
"It's always disappointing to see athletes involved in such activity as we want to see athletes compete with the fairness and integrity of sport maintained."
Last week the IAAF provisionally suspended the manager of the Kenyan athletics team "in relation to potential subversion of the anti-doping control process" in the country.
Michael Rotich allegedly agreed to provide advanced warning of drugs tests in return for a £10,000 bribe and was subsequently been sent home.
In the same week, Kenyan sprinting coach John Anzrah was dismissed from Rio 2016 after allegedly attempting to swap an athlete's urine with his own.