Usain Bolt says athletes who dope must "stop or the sport will die" as he prepares to race for the final time in his illustrious career.
Bolt, an eight‑time Olympic champion and icon of world sport, will retire after this month's World Championships.
The Jamaican will run in the 100m and 4x100m at the Worlds, which begin in London on Saturday.
He says hopefully athletes will see what is going on and what they need to do to help the sport move forward.
Bolt added that he is still the fastest in the world.
Bolt says he will miss the "thrill" of being on the track but that it is time for him to slow down and enjoy himself.
Source : BBC
