Burundian Runner Francine Niyonsaba said on Instagram she had signs of a stress fracture a month ago and, although she was almost fully recovered, she missed too much training. She added that she was “extremely sorry” to withdraw.
Niyonsaba is a former Olympic 800 meter silver medallist who was barred from competing in that event due to World Athletics regulations controlling athletes with intersex disorders known as 46,XY variations in sex development.
Niyonsaba won the 5,000m race at the Diamond League final last last September, beating two-time world champion Hellen Obiri of Kenya.
She qualified for the 5,000 final at last year's Tokyo Olympics only to be disqualified after her heat because of a lane infringement. She has said it was an unfair disqualification.
In Tokyo, Niyonsaba also finished fifth in the 10,000 meters final and entered the 5,000 and 10,000 at the worlds in Eugene, Oregon.