Some of Russia's best known track and field athletes are facing doping cases, including former Olympic high jump champion Ivan Ukhov.

The Athletics Integrity Unit, which oversees anti-doping cases in track and field, released details on Friday of 109 cases from around the world in a new transparency drive.

Besides Ukhov, the list includes top Russians such as the double world champion shot putter Tatyana Lysenko, Olympic bronze medal-winning long jumper Svetlana Shkolina, and 2014 world indoor triple jump champion Lyukman Adams.

The AIU said they are among 13 Russian cases based on evidence uncovered during World Anti-Doping Agency investigator Richard McLaren's research into a widespread system of doping and cover-ups in Russia.

The cases of Ukhov, Lysenko, Adams, and Shkolina are all listed as pending before the Court of Arbitration for Sport.

Some of the 13 have competed in recent months, and the AIU said they weren't suspended ahead of a hearing.

"Where there is a case that doesn't involve a positive test but is the result of an investigation based on McLaren evidence only, the athlete can continue to compete until their case is determined," the AIU said in emailed comments to The Associated Press.

There's also a case against two-time world championship medalist Anisya Kirdyapkina based on suspicious blood values in samples she gave to drug testers.

Kirdyapkina was on Russia's national race-walking team during a time when doping was widespread, leading to bans for more than 30 athletes, including her husband Sergei Kirdyapkin, and a life ban for the head coach Viktor Chegin.

Among athletes from outside Russia, the AIU release also revealed reigning Olympic women's marathon champion, Kenyan runner Jemima Sumgong, faces another doping hearing on allegations of "tampering" with a drug test. Sumgong is already banned until 2021 after testing positive for the banned drug EPO last year.