Justin Gatlin will lead a 130-strong US team at the World Championships in Beijing, with world silver medallist Nick Symmonds the notable absentee. Gatlin is the fastest man in the world this year over 100m and 200m and his showdowns with defending champion Usain Bolt are eagerly anticipated. Symmonds has been left out after refusing to sign a mandatory contract. Galen Rupp, the 10,000m Olympic silver medallist, will compete in the 5,000m and 10,000m in the Bird's Nest. The 29-year-old has recently faced doping allegations, along with his coach Alberto Salazar. Both Rupp and Salazar, deny any wrongdoing. Other prominent American athletes competing in the championships, which begin on 22 August, are Olympic 200m champion Allyson Felix (200m, 400m and relay) and reigning world decathlon champion Ashton Eaton. 

 Also athletes could be falsely accused of cheating if blood data is not analysed correctly, the head of UK Anti-Doping (Ukad) has warned. The Sunday Times published data from 5,000 athletes, which it says reveals an "extraordinary extent of cheating". But Ukad chief executive Nicole Sapstead says other factors must be taken into account to ensure accuracy.