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The Transgender Sports Issue

Recently, Pete Buttigieg tried to assert that the transgender sports issue is “complex” and that the voices of those who oppose trans girls in sports should be heard too. I suppose you could claim the issue is “complex” but there’s already a great deal of scientific research about this that’s complete. Some of the studies included large numbers of trans athletes too, so the results are something to think about. Let’s look at a few of the largest of those studies.

The US Air Force conducted two studies about transgender athletic performance, using transgender and cisgender service members. Service members are in considerably better physical condition than the rest of the United States because they have to be. They take and must pass physical fitness tests multiple times per year. Failure to pass usually means the soldier in question has a limited time to retake and pass the test or be discharged from the service for failure to meet the physical requirements associated with military service.

So service members provide an excellent proxy for athletes and there is a large number of them that can be evaluated to get reasonable samples. So what did the Air Force find about transgender service members?

First, before beginning hormone replacement therapy (HRT), transgender women consistently performed worse than cisgender men. After one year of hormone therapy, transgender women performed worse than with no hormone therapy but still better than cisgender women. But by two years of HRT, transgender women performed in the same range as cisgender women in every category measured, except one. Even their bone density lessened until it was the same as cisgender women’s bone density. Their VO2 max lessened until it was in the same range as cisgender women.

Now, to be specific, in the smaller Air Force study conducted by TA Roberts, J Smalley, and D Ahrendt, after 2 years, trans women showed a minor run speed advantage but performed otherwise the same as cisgender women in all other tests. In the larger study, done by E. Chicarelli, J Aden, D Ahrendt, and J Smalley, the run speed advantage vanished when examined across a larger sample size. I’ve provided a link to the study below which is from the National Library of Medicine. Further, the larger study went on to the four years mark of HRT as well, however, many of the transgender service members chose to leave the service and were not available for comparison in the four year data sample.

This wasn’t a unique result either. The International Olympic Committee has studied this multiple times and found no basis to support any claim that transgender women will outperform cisgender women. In fact, in April 2024, the IOC released another study that said that, based on the data measured, transgender women not only did not perform better than cisgender women in elite athletics but the data suggested that trans women are actually at a minor handicap in elite athletics vs cisgender women. Trans women athletes tend to have more body fat and less lean muscle mass than cisgender women athletes. The IOC did find that trans women retained an advantage in grip strength though.

So what the science is telling us, repeatedly, is that in most sports, trans women do not have a significant advantage over cisgender women. This is especially true of team sports like basketball, volleyball, and soccer. You can argue that more specific research needs to be done but anyone making the blanket claim that trans women should be banned from all women’s sports is simply talking from a position of ignorance and bigotry.

Finally, what has not been done is any sort of analysis on trans girls who never undergo male puberty. That’s a study that likely needs to be done. However, as someone who coached youth soccer for years, I can state that I very often found pre-pubescent cisgender girls to be more athletic than the pre-pubescent cisgender boys. That’s anecdotal but it’s a common observation. What we don’t currently have (to the best of my knowledge) are any significant studies on the impacts of puberty blockers and HRT on trans kids who do not then experience their biological puberty.

We can give Pete the benefit of the doubt on this because it is a nuanced issue and it does need more study. However, I think we can authoritatively agree that total bans on trans women and trans girls in all women’s sports is not based on science, and has more to do with bigotry and hate than with anything scientific.

REFERENCES:

The Impact of Gender-Affirming Hormone Therapy on Physical Performance

Strength, power and aerobic capacity of transgender athletes: a cross-sectional study

Biology Is A Shit Show

This has been posted elsewhere many times over the years and was composed by Rebecca Helm, a biologist and assistant professor at the University of North Carolina (at least at the time this was written).

Rebecca Helm, a biologist and an assistant professor at the University of North Carolina, Asheville US writes:

Friendly neighborhood biologist here. I see a lot of people are talking about biological sexes and gender right now. Lots of folks make biological sex sex seem really simple. Well, since it’s so simple, let’s find the biological roots, shall we? Let’s talk about sex…[a thread]

If you know a bit about biology you will probably say that biological sex is caused by chromosomes, XX and you’re female, XY and you’re male. This is “chromosomal sex” but is it “biological sex”?

Well…

Turns out there is only ONE GENE on the Y chromosome that really matters to sex. It’s called the SRY gene. During human embryonic development the SRY protein turns on male-associated genes. Having an SRY gene makes you “genetically male”. But is this “biological sex”?

Sometimes that SRY gene pops off the Y chromosome and over to an X chromosome. Surprise! So now you’ve got an X with an SRY and a Y without an SRY. What does this mean?

A Y with no SRY means physically you’re female, chromosomally you’re male (XY) and genetically you’re female (no SRY). An X with an SRY means you’re physically male, chromsomally female (XX) and genetically male (SRY). But biological sex is simple! There must be another answer…

Sex-related genes ultimately turn on hormones in specifics areas on the body, and reception of those hormones by cells throughout the body. Is this the root of “biological sex”??

“Hormonal male” means you produce ‘normal’ levels of male-associated hormones. Except some percentage of females will have higher levels of ‘male’ hormones than some percentage of males. Ditto ditto ‘female’ hormones. And…

…if you’re developing, your body may not produce enough hormones for your genetic sex. Leading you to be genetically male or female, chromosomally male or female, hormonally non-binary, and physically non-binary. Well, except cells have something to say about this…

Maybe cells are the answer to “biological sex”?? Right?? Cells have receptors that “hear” the signal from sex hormones. But sometimes those receptors don’t work. Like a mobile phone that’s on “do not disturb’. Call and call, they will not answer.

What does this all mean?

It means you may be genetically male or female, chromosomally male or female, hormonally male/female/non-binary, with cells that may or may not hear the male/female/non-binary call, and all this leading to a body that can be male/non-binary/female.

Try out some combinations for yourself. Notice how confusing it gets? Can you point to what the absolute cause of biological sex is? Is it fair to judge people by it?

Of course you could try appealing to the numbers. “Most people are either male or female” you say.

Except that as a biologist professor I will tell you…

The reason I don’t have my students look at their own chromosome in class is because people could learn that their chromosomal sex doesn’t match their physical sex, and learning that in the middle of a 10-point assignment is JUST NOT THE TIME.

Biological sex is complicated. Before you discriminate against someone on the basis of “biological sex” & identity, ask yourself: have you seen YOUR chromosomes? Do you know the genes of the people you love? The hormones of the people you work with? The state of their cells?


Since the answer will obviously be no, please be kind, respect people’s right to tell you who they are, and remember that you don’t have all the answers. Again: biology is complicated. Kindness and respect don’t have to be.


Note: Biological classifications exist. XX, XY, XXY XXYY and all manner of variation which is why sex isn’t classified as binary. You can’t have a binary classification system with more than two configurations even if two of those configurations are more common than others.

Biology is a shitshow. Be kind to people.