Debate rages after transgender swimmer makes sporting history

Transgender swimmer Lia Thomas has sparked more ugly backlash after creating history at the US collegiate championships in Atlanta.

The University of Pennsylvania swimmer has been in the headlines a lot recently after breaking a number of college records in the United States.

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Thomas shrugged off the protesters as she powered to a historic victory in the 500-yard freestyle at the US collegiate championships, to mark the latest milestone in her career.

The win saw Thomas become the first transgender athlete to win a National Collegiate Athletic Association (NCAA) top tier title after touching the wall in 4mins 33.24secs, more than a second-and-a-half clear of Virginia's Emma Weyant, who finished in 4:34.99.

Erica Sullivan, a silver medalist in the 1500m at the Tokyo Olympics last year, was third in 4:35.92.

Thomas has dominated US collegiate women's swimming recently as a student athlete at Penn, where just a few years ago she competed as a man.

Since joining the women's team, Thomas has broken two school records and posted the fastest times in the country in the 200 and 500-yard freestyle events. Now she's an NCAA champion.

Her case has divided opinion, with some - including several teammates - arguing she has an unfair physiological advantage and should be barred from competing, while others say she should be allowed to compete freely as a woman.

Sixteen members of her 40-strong Penn team signed a letter arguing she had obtained an "unfair advantage."

However, more than 300 current and former swimmers signed an open letter calling for Thomas to be allowed to compete.

Before the latest meet in Atlanta, a small number of protesters gathered outside the venue to demonstrate against Thomas's participation, waving banners that read "Support Fair Sports for Women and Girls" and "Stand Up 4 Women."

Speaking after her victory on Thursday, Thomas said she was determined to block out the negativity and concentrate on her own performance.

"I try to ignore it as much as I can, I try to focus on my swimming, what I need to do to get ready for my races and try to block out everything else," Thomas said after the race at the McAuley Aquatic Center.

"I didn't have a whole lot of expectations for this meet. I was just happy to be here, trying to race and compete as best as I could.

"It means the world to be here, to be with two of my best friends and teammates and to be able to compete."

Lia Thomas receives subdued applause after victory

After the race, Thomas received a ripple of subdued applause after she was announced as the winner, in a pointed contrast to the loud cheering that greeted other leading finishers in the race.

Thomas had advanced to the final after posting the quickest time in morning preliminaries.

She is also a strong contender in Friday's 200 freestyle, where she has the top seeding with a time of 1:41.93. She is seeded 10th in the 100 free at 47.63.

Last month, the governing body of swimming in the United States, USA Swimming, unveiled new guidelines which include a more stringent threshold for testosterone.

Although not mentioning Thomas by name, the rules were widely seen as an attempt to make it harder for her to compete at this week's championships.

However, the NCAA, the governing body for US college sport, subsequently announced that the new rules - and the new USA Swimming testosterone standard - would not be applied to the championships, saying to do so would have "unfair and potentially detrimental impacts" on athletes preparing for the meet.

Among Thomas' supporters was Olympic medalist Sullivan, who finished third behind the transgender swimmer in Atlanta.

Sullivan has been a staunch supporter of Thomas, comparing it with her own decision to come out as gay.

"I was fortunate enough to be welcomed with open arms in the swim community when I came out as gay," Sullivan said in a statement.

"Just with my own personal good experience of coming out and feeling all that love and support within my swim community, I feel like Lia deserves the same thing."

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