Belgian Hanne Maudens pictured in action during the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO DIRK WAEM

A pole vault athlete pictured in action at the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO DIRK WAEM

Great Britain Laura Muir reacts after the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO JASPER JACOBS

Illustration picture shows the 'Play True Day' anti-doping action by Sport Vlaanderen at the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO JASPER JACOBS