Several parents of University of Pennsylvania swimmers are speaking out about a high-profile transgender athlete who has broken multiple records, arguing that the NCAA must change its rules in order to bring fairness back to meets for biological females.

At issue is University of Pennsylvania swimmer Lia Thomas, a transgender woman who formerly competed for the men's team but now swims in women's meets. Thomas, who was born male, set pool, meet and program records in December at the Akron Zippy Invitational in the 1,650-yard freestyle, the 200 freestyle and the 500 freestyle.

Thomas' winning times have sparked a nationwide debate about transgender athletes - particularly about transgender women who formerly trained as men. For example, Thomas' won the 1,650 by more than 38 seconds and the 200 free by more than seven seconds. Thomas' times in the 200 and 500 were the best in the country this season.

Over the weekend, Thomas won the 200 freestyle and the 500 freestyle at a three-team meet.

"It starts with the NCAA," two parents of an unidentified Penn female swimmer told Fox News. "I think the NCAA needs to change its policies and find a way to include transgender women without trampling all over biological women."

Sue Feldman, another swimming parent, said: "I think that this is obviously an issue, and they should probably just look at how they're going to handle it and maybe handle it better in the future because right now they're not handling it so well."

Thomas is on pace to win NCAA championships and set NCAA records, according to Donna Lopiano, president of Sports Management Resources and an adjunct professor of sports management at Southern Connecticut State University.

"[Thomas is] swimming extraordinarily fast women's times that are on course for breaking collegiate national records set by the likes of Katie Ledecky in the 500-yard freestyle and Missy Franklin in the 200-yard freestyle," Lopiano wrote at Forbes.com.

One problem, Lopiano said in agreeing with the parents, is the NCAA rule governing transgender athletes. The NCAA requires male-to-female athletes to undergo one year of testosterone suppression treatment but does not set a benchmark.

"There is no specified testosterone (T) level down to which the athlete must suppress their testosterone," Lopiano wrote. "There is no specified degree of mitigation that must be achieved during this period. For example, such a standard might be 'reduction of pre-transition male testosterone level into the female range for 12 consecutive months' or 'testosterone levels not exceeding 3 nmol/l' for the specified time period."

The female testosterone range is .06 to 1.68 nmol/l, while the "male range starts much higher, at 7.7, and goes up to 29.4 nmol/l," Lopiano wrote.

Lopiano questioned whether Thomas had physical qualities that could not be suppressed. For example, Thomas' best time in the 200 freestyle as a male was only 2.64 percent faster than Thomas' time as a female. By contrast, there is an 11.87 percent difference between men and women in the NCAA qualifying standard for the 200 freestyle. In other words, there should be nearly a 12 percent difference between men and women in the event. For Thomas, though, it's less than 3 percent.

"If a transgender woman athlete does not wish to take hormones or to surgically change her body or has not achieved sufficient mitigation to permit fair or safe competition against females, we must design a competition accommodation that guarantees her inclusion within women's sports," Lopiano wrote. "We must be able simultaneously to guarantee fair and safe competition for the female category (to include transgender boys who do not wish to change their bodies) and adhere to social justice principles of inclusion for all girls and women."