A US world champion track runner is speaking out against athletes assigned male at birth competing against women, warning that ‘if male-bodied athletes continue competing on female teams, it will be the end of women’s sports.’

Cynthia Monteleone, 45, is one of the US’ foremost Masters athletes and a world champion in the 400m, but detailed her near-loss to a transgender runner in 2018, and her runner daughter’s loss to a transgender athlete in an opinion piece published on Friday by Fox News.