A champion female cyclist has quit the sport after constant beatings by transgender athletes, admitting in a heartbreaking message: 'I lose no matter how hard I train.'

Hannah Arensmen, a 35-time winner on the national cyclocross circuit, revealed her ordeal in an amicus brief to the Supreme Court in support of legislation in West Virginia which seeks to ban transgender student athletes from competing outside their biological gender.

An injunction by a lower court is currently barring the law from being enforced over claims that it violates Title IX federal sex discrimination protections in education.

Arensmen is among 67 athletes, coaches and family members who have asked the Supreme Court to intervene, and provides a moving account of how she felt has 'overlooked and humiliated' as she has been bested in races by male-born athletes.

It comes as transgender cyclist Tiffany Thomas, 46, blew the competition of out of the water at the Randall's Island Crit event in New York over the weekend. Thomas, who only took up cycling in 2018, is 14 years older than her eldest teammate.

Writing in her amicus brief to the Supreme Court, Arensmen said: 'I was born into a family of athletes. Encouraged by my parents and siblings, I competed in sports from a young age, and I followed in my sister's footsteps, climbing the ranks to become an elite cyclocross racer.

'Over the past few years, I have had to race directly with male cyclists in women's events.

'As this has become more of a reality, it has become increasingly discouraging to train as hard as I do only to have to lose to a man with the unfair advantage of an androgenized body that intrinsically gives him an obvious advantage over me, no matter how hard I train.