Nine-times Olympic champion Carl Lewis has called on athletics governing bodies to stop any athletes who have failed doping tests from coaching.
The American also says athletes should not be allowed to coach without proper training and certification.
Lewis says it's a huge problem in the sport that needs immediate attention and both the International Association of Athletics Federations and national federations should take action.
Lewis, who won the Olympic 100 metres title twice and the long jump four times, says if an athlete tests positive and retires they should be banned from coaching for life.
He says there's no other sport in the world that would allow someone to compete one year and coach a professional athlete the next year.