Olympic 50 kilometre walk champion Sergei Kirdyapkin and two other Russian Olympic gold medalists were on Tuesday banned by the Russian anti-doping agency.
Kirdyapkin, who won his gold in a record time, Olga Kaniskina and Valery Borchin, who won the women's and men's 20km respectively in Beijing 2008, were all suspended for abnormal indexes of haematological profiles in their biological passports.
The same punishment was meted out to 2011 50km world champion Sergei Bakulin.
Kirdyapkin, Kaniskina, who has already retired, and Bakulin were all banned for 38 months. Borchin was banned for eight years as a repeat offender.
All bans were backdated to October 15, 2012, meaning Kirdyapkin will be able to defend his title at the 2016 Rio Games.
Vladimir Kanaikin, silver medalist at the 2011 world championships and who has already served a two-year ban in 2008-10, was banned for life from December 17, 2012.
The bans were announced on the Russia doping agency's official site.
Tuesday's ruling does not include results at the 2012 Olympics, except for Borchin's, who failed to finish in London.
Source: AFP