As the global sporting community reacted with shock to a mass doping case in China, the East Asian nation's swimmers shrugged off the furore at Olympic trials to post a series of eye-catching times in the lead-up to Paris.

The World Anti-Doping Agency has said it stands by its decision to clear more than 20 Chinese swimmers who tested positive for a banned heart medication before the 2021 Tokyo Olympics.

The world's top anti-doping regulator says after reviewing a documentary and other media reports that it stands by the results of its decision to clear 23 Chinese swimmers to compete at the Tokyo Olympics despite testing positive for a banned heart medication.