She and others are upset because today, some transgender women, people born male but who identify as female, are winning sports competitions.
Schneeberger regularly won bicycle races, until a former men's cyclist transitioned, competed as a woman, and rode away from her.
"How did this happen?" asks Schneeberger. "I just want to be able to compete on a fair playing field."
But no playing field is perfectly fair, says trans athlete Joanna Harper.
Harper is also a scientist who advised the Olympic committee. She points out that transgender competitors often take testosterone blockers that help align their body with how they identify. As a result, "Trans women lose muscle, lose strength, lose endurance."
"Within nine months of my starting hormone therapy," she says, "I was running 12% slower."
That's why sport organizations like the Olympics and NCAA require trans athletes to undergo hormone therapy.
Trans sprinter Cece Telfer, who won an NCAA championship, says, "As a trans athlete, I am not a threat to women's sports. Because I am a woman!"
But before Telfer transitioned, when she competed as a man, she wasn't the champion she is now. She ranked 390th best. I point that out to Harper.
"I have to admit I am somewhat at a loss to explain it," Harper responds. "However, there are hundreds of NCAA championships awarded every year. ... The idea that trans women are hugely going to outperform ciswomen does not hold up to the statistics."
Yes, it does, says biologist Emma Hilton who co-authored a review on trans women in sports.
She found that in most every category, men are much stronger. Testosterone blockers just can't close the gap.
"A male could be 40% stronger than a female on his legs," she says. "Things like shoulder width don't change when transgender women suppress testosterone. They don't get shorter. Their hearts don't get smaller. They've still got big lungs. The performance gap in weightlifting is over 30% ... throwing a baseball over 50% ... when a male punches, 160%."
I support adults who want to transition. People should be allowed to be whoever they want to be. But why should they be allowed to compete in top level events like the Olympics? This year, there was only one trans woman competing, a weightlifter from New Zealand. She didn't win a medal.
But in the future, there will probably be more. I think that's unfair.
Harper disagrees. "Trans women will not be outperforming cisgender women by such a margin in most sports that we can't have reasonable competition."
She says sports already allow for certain advantages. Some players are taller; some have better coaching. "Richer nations win the majority of Olympic medals."
Still, few female competitors consider transwomen's advantage "reasonable."
The New Zealand weightlifter who lost her spot to the trans athlete didn't think it was fair, but said she and others were told to stay quiet about it.
Athletes won't speak up, says Schneeberger, because "they don't want to lose sponsorship opportunities (or) be called a bigot."
Currently, most states, supported by the Biden administration, allow trans student athletes to compete, even without hormone therapy.
As a result, some trans athletes now dominate some high school girls' sports. In Connecticut, two transgender sprinters won 15 championships.
It's "not because they were trans that they were winning; they were just faster!"says Veronica Ivy, a trans athlete who won bike sprint championships. "These fears that trans women are a threat to women's sport are irrational fears of trans women."
"That's an attempt to shut down conversations," biologist Hilton replies, "and stop people from asking questions."
It's working. Many female athletes smile on the podium, raging inside, but remaining silent for fear of losing sponsorships and prize money.
"It's not fair," says Schneeberger. "To watch a transgender female ride away from me like it was nothing, and there's nothing I can do about it, it was torture. I really haven't raced since."