Transgender NCAA swimming champion Lia Thomasis firing back at those claiming her dominance is unfair to biological women ... saying trans athletes will not destroy women's sports.
The University of Penn athlete broke her silence on "Good Morning America" on Tuesday ... saying she knew she'd face backlash once she started competing against women, but no amount of scrutiny would stop her.
"I was prepared for that, but I don't need anyone's permission to be myself and do the sport that I love," she said.
Many have denounced Thomas' participation in women's sports after she finished first in the women's 500-yard freestyle back in March ... with everyone from Caitlyn Jenner to Florida governor Ron DeSantis to Joe Rogan, who called it "an assault on women's sports."
But, Thomas argues that shouldn't be the case ... saying, "Transitioning to get an advantage is not something that ever factors into our decisions."
"Trans women are not a threat to women's sport."
EXCLUSIVE: "Trans people don't transition for athletics. We transition to be happy and authentic and our true selves."