Sebastian Coe says athetics "is about a great deal more than doping," adding: "We've chased some of the biggest names out of the sport, and that doesn't come without a cost."
Andrew Redington/Getty Images Europe/Getty Images
But track and field athletics has come under scrutiny after fresh claims of widespread doping at major championships.
Glenn Hunt/Getty Images
The Sunday Times and German broadcaster ARD have accused the International Association of Athletic Federations (IAAF) of failing to investigate hundreds of "suspicious" drug tests between 2001 and 2012.
Robert Cianflone/Getty Images/file
The reports said 800 of the 12,000 blood tests involving 5,000 athletes were suspicious.
Al Bello/Getty Images/file
The IAAF has denied athletics is suffering a similar crisis to cycling's past history of doping when that sport was bedeviled by extensive drug-taking and accusations of top-level cover-ups.
Kevork Djansezian/Getty Image/file
Coe -- twice Olympic 1,500 meter champion -- insists the organization has led the way on out-of-competition independent testing.
Staff/AFP/Getty Images/file
Former pole vaulter Sergey Bubka, who is standing against Coe in August to become the next IAAF president, says athletics "must be more proactive and even more transparent in our aggressive pursuit of a zero tolerance policy against doping cheats."
KIRILL KUDRYAVTSEV/AFP/Getty Images
The head of the International Olympic Committee (IOC) Thomas Bach has promised the organization will pursue a policy of "zero tolerance" if allegations of widespread doping by track and field athletes at the Olympics are proven.
Tony Barson/Getty Images Europe/Getty Images
This isn't the first time that athletics has faced questions over doping. Ben Johnson stunned the world by taking 100m gold in a record time in South Korea at the 1988 Olympics, but the Canadian left the Olympic movement in turmoil when he later tested positive for a banned substance.