There’s an odd asymmetry in how Shermer and Shrier think about transgender athletes. They talk exclusively about transgender women entering women’s sport, but ignore the possibility of transgender men entering men’s sport. A sample:

[1:00:47] SHRIER: Sometimes people look at the numbers and they say there aren’t that many transgender kids, so there’s no reason for the moral panic. Who cares if the number one, two, and three spots go to biological boys? First of all, there’s obviously the incredible unfairness of fixing the race … telling girls “oh, you’ll never ever, no matter what you do, no matter how hard you train, you will never be number one. You will never make regionals.”… That’s a very different prospect for young women … [1:01:19]

So being assigned female doesn’t offer any advantages in any sport? At all? Let’s make a case for a female advantage. I’ll point out the logical and rhetorical flaws I’m deploying via tool-tips.

For now, elite ultrarunning is one of the few sports in which women appear able to hold their own with men. [Courtney] Dauwalter’s prowess has crystallized the debate about whether psychological fortitude can trump men’s innate strength advantages in endurance sports. This much is clear: As the distance lengthens, the biological advantages that men have grow smaller. […]
“We know that men are simply bigger and have more muscle mass and are more powerful and faster,” said Heather Heying, an evolutionary biologist. But, she added, “This is about stamina, and stamina is some combination of yes, strength, but also psychological will. It begs the question, is there something going on for women perhaps given our very long evolutionary history as mammals who spent a long time gestating and then giving birth, that gives us a psychological edge in extremely long-term endurance events?”

There’s a not-insignificant amount of evidence that cis women are better at endurance sports than cis men. And not just at running.

We investigated performance and sex difference in performance for successful women and men crossing the ‘Catalina Channel’ between 1927 and 2014. The fastest woman ever was ~22 min faster than the fastest man ever. Although the three fastest women ever were ~20 min faster than the three fastest men ever, the difference reached not statistical significance (p > 0.05). Similarly for the ten fastest ever, the ~1 min difference for women was not significant (p > 0.05). However, when the swimming times of the annual fastest women (n = 39) and the annual fastest men (n = 50) competing between 1927 and 2014 were compared, women (651 ± 173 min) were 52.9 min (16 ± 12%) faster than men (704 ± 279 min) (p < 0.0001).

Knechtle, Beat, Thomas Rosemann, and Christoph Alexander Rüst. “Women Cross the ‘Catalina Channel’ Faster than Men.” SpringerPlus 4 (July 8, 2015). https://doi.org/10.1186/s40064-015-1086-4.

Most studies focusing on isotonic-like tasks have focused on the elbow flexors and/or knee extensors (Maughan et al. 1986, Pincivero et al. 2004, Labarbera et al. 2013, Senefeld et al. 2013, 2016, Yoon et al. 2015) and have reported less (Maughan et al. 1986, Labarbera et al. 2013, Yoon et al. 2015) or similar (Maughan et al. 1986, Pincivero et al. 2004, Senefeld et al. 2013, 2016) fatigability for females compared with males. During controlled, slow velocity, low resistance contractions, females exhibited less fatigue than males (Labarbera et al. 2013; Maughan et al. 1986; Yoon et al. 2015), but as the load (Maughan et al. 1986) or angular velocity is increased (Senefeld et al. 2013) sex-related fatigability is similar. However, when fatigability was characterized by a maximal voluntary isometric contraction (MVC) following maximal unconstrained velocity knee extensions, females were less fatigable than males (Senefeld et al. 2013).

Lanning, Amelia C., Geoffrey A. Power, Anita D. Christie, and Brian H. Dalton. “Influence of Sex on Performance Fatigability of the Plantar Flexors Following Repeated Maximal Dynamic Shortening Contractions.” Applied Physiology, Nutrition, and Metabolism 42, no. 10 (June 21, 2017): 1118–21. https://doi.org/10.1139/apnm-2017-0013.

In both long-distance swimming and synthetic tests, cis women can have a performance advantage over cis men. There’s also the issue of Relative Energy Deficiency in Sport.

Low Energy Availability, which can result when athletes consume less fuel than they are using, is a primary cause of RED-S, formerly known as Female Athlete Triad syndrome, in which disordered eating, loss of menstruation and osteoporosis occur, but can also contribute to reduced testosterone levels and libido in men, poor bone health, increased risk of illness and injury, gastrointestinal disturbances, cardiovascular disease, impaired training capacity and performance.

Women are already acutely aware of bone loss and similar issues, while men rarely visit the doctor and are unlikely to seek treatment. This hurts their performance in endurance sport.

This is actually a problem, as most sport is endurance-based. Soccer, hockey, rugby, gymnastics, handball, sailing, climbing, biathlon, cross-country skiing, endurance running, swimming, pentathlon, basketball, rowing, triathlon, downhill skiing, and nordic combined all depend heavily on endurance, and thus could be enhanced by “female puberty.” Better endurance also means less drain on other body systems, such as the brain, so these athletes might have a strategic advantage over others.

Not everything is rosy, though. For instance, there’s some weak evidence that increased estrogen can reduce endurance. This, however, is where transgender men leap ahead of their cis counterparts. The typical course of treatment for them is testosterone injections, and those have a triple impact (emphasis mine):

Testosterone (sometimes called “T”) is the main hormone responsible for promoting “male” physical traits, and is usually used for hormonal “masculinization” in FTMs. Testosterone works directly on tissues in your body (e.g., stimulating clitoral growth) and also indirectly by suppressing estrogen production. If your menstrual periods don’t stop within three months of taking testosterone, Depo-Provera® (a type of progestagen) can be injected every 3 months until the testosterone kicks in.

Transgender men don’t just bulk up due to the testosterone, their periods stop and estrogen levels drop. They get to have muscles and improved endurance, and even if estrogens would impact the latter they’re still protected from its effects. It’s pretty clear they have an advantage in most sports over their cis male-

… Okay, OUCH, that whole section was a pain to type out. You get the picture, though. Shrier and Shermer could have easily constructed an argument that transgender men had an advantage in some sports, and thus are worthy of exclusion in the male category. So why the double standard? Many transphobes forget that transgender men exist, but Shrier instead makes them a centerpiece of her arguments. No, the most likely reason is less charitable. Emphasis mine.

[57:17] SHERMER: When men can just say “I’m a woman now,” and even if they really do identify as a woman and they’ve taken … hormone blockers and whatnot for a year … but when you see them, clearly, they’re not women. They’re much larger, their bones are bigger, they just have the amount of strength you get from having bigger tendons here [points to forearm] than a woman would have, and that’s not going to change in a year or two. It may never change.

[57:57] SHRIER: That’s right. There are organizational effects of testosterone that occur during puberty, and they confer a
permanent advantage. Even if you lower activational hormones in the body later … you can’t undo the permanent lifetime effects of larger hearts, as you said, larger bones, more muscle mass, more fast twitch muscle fiber.

Shrier explicitly states that all men are either superior or equal to all women when it comes to sports. Shermer agrees with her. That’s good ol’ fashioned sexism, hidden behind a fresh coat of paint.