CAS Clears Koki Ikeda and Restores Japanese Race Walker’s Eligibility

The Court of Arbitration for Sport has upheld Japanese race walker Koki Ikeda’s appeal against World Athletics, overturning his four-year sanction and clearing him of an anti-doping rule violation.

The decision makes the 28-year-old immediately eligible to compete again. CAS found that abnormal readings in Ikeda’s Athlete Biological Passport had a reasonable explanation unrelated to doping and concluded that the charge had not been established.

CAS overturns original ruling

Ikeda’s case involved an allegation of blood manipulation based on changes identified in his biological profile. CAS said several readings were abnormal but accepted that there was a reasonable non-doping explanation for the findings.

The appeal body also said Ikeda presented substantial medical and expert evidence, giving the case a broader factual basis than had been available during the earlier proceedings before a World Athletics tribunal.

Ikeda was provisionally suspended in November 2024 and received the four-year sanction in February 2025. He was also barred from competing at the Japan Race Walking Championships. Under the original ruling, his results from June 20, 2023, through November 1, 2024, were disqualified.

He challenged the ruling at CAS in March 2025, and the case was heard in Lausanne in May. CAS concluded that no ban should apply.

Ikeda won silver in the 20km race walk at the Tokyo Games and at the 2022 World Championships in Eugene. He finished seventh in the same event at the 2024 Paris Olympics.

AIU announces separate ban for Aga

In a separate case, the Athletics Integrity Unit said Ethiopian marathon runner Ruti Aga had received a six-year ban for the presence or use of methylprednisolone and for tampering with evidence.

According to the AIU, the first two years of the sanction followed a positive test for methylprednisolone. A further four years were added after the organisation said Aga misled investigators during an interview and submitted a fake prescription to justify her use of the substance.

The AIU said Aga tested positive in March after winning a half marathon in China. Her provisional suspension began on September 10, the date from which the ban runs.

Aga, 32, won the 2019 Tokyo Marathon and has finished second three times and third twice at World Marathon Majors.