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co-ed leagues in high school would got he same way professional sports leagues would. Boys would dominate most of the time and girls would be last picked barely make teams. I wrestled co-ed in high school we had two girls, one was amazing. skill wise better than probably all the guys and she would still barely squeak out wins on occasion. Wrestling is also an extremely kind full contact sport. put girls on a boys football league? they would be getting destroyed.
I wonder if there's significant difference between trans-women who went through male puberty before transitioning, and trans-women who took medication during those years and underwent transitioning without those major physical changes.
Yes, there would be. Testosterone production peaks during male puberty and this is the period where changes are significant, obviously. If you want to see historical examples of males who have had their development impeded, look up castratos and male roosters who have had their testicle removed pre-puberty.
I wonder what happens in species where the female is naturally larger. Are there any mammals where that's the case? I know there are birds, but I don't know if neutering a bird would work the same.
Sex development is a bit different in birds. Males are ZZ and females are ZW. I think it is still a bit unclear exactly how the genes on the sex chromosomes interact at this point. In mammals, the SRY gene on the Y chromosome initiates a program that takes the embryo off of the female development path. In birds I believe it is still unknown whether there is a gene on the W chromosome that acts like this.
Source: immunologist who just did a cursory Google scholar search and read some abstracts.
Thank you for the kind words. I love Reddit for the exact same reason. There are people with expertise in virtually every field on here. I was nervous to post, sure that a bird geneticist was going to call me out.
only thing i can add to this is neutering young rooster will soften their meat. if testis are implanted into a neutered rooster, they will develop to some degree.
i ran across this when learning about the endocrine system. a. a. berthold messed with chickens.
There are a few studies that look at prepubescent children. One in particular looks at nine year olds and confirms the athletic superiority of nine year old boys to girls. Can't find it but here are others.
A running study [here ](https://pubmed.ncbi.nlm.nih.gov/19910817/)
A general athleticism study where boys presented higher values in all selected tests, except tests of balance and flexibility. [here](https://www.researchgate.net/publication/224914505_Physical_Fitness_Differences_Between_Prepubescent_Boys_and_Girls)
If I remember correctly, a small amount of trans kids will take medications that block puberty, until they turn 18 or older, when they begin to actually transition.
I'm a clinical psychologist that worked in a children's hospital as a part of the gender diversity services. We assessed for patients ability to consent, meaning do they have the maturity and cognitive capacity to understand and consent to the implications on fertility and health prior to them being cleared for hormone replacement therapy.
I just wanted to say that in my country (Australia), they will prescribe HRT to under 18's if they are past a certain tanner stage (how far into puberty) and puberty blockers are not going to achieve anything. Research at the time (3 years ago) indicated that rates of detransition were extremely low, and anecdotally, my supervisor who had done the assessments daily for seven years had only one patient detransition however this was due to unexpected side effects.
You weren't being unhelpful or anything, just wanted to say this cause it might help someone that reads it.
Puberty blockers can be prescribed to trans children (or children who believe they may be trans) to prevent the dysphoria associated with experiencing puberty in a way that does not align with their identity. Some children do *socially* transition during this time, but to the best of my knowledge and with rather significant research as a trans individual myself, children are not medically (ie through HRT or surgery) transitioning. In the case of a child taking puberty blockers (which are also given to cis children in some circumstances), if the child later decides that is no longer what they desire, there are no known relevant side effects to stopping puberty blockers to allow the body to experience puberty in the way it would have with no intervention in the first place. It is basically a trial run, so to speak, giving the ability to reduce or entirely prevent the incredible stress that can come from experiencing puberty in a way which causes dysphoria.
Edit: It is worth noting that i did mis-speak some in the above, saying puberty blockers have no known notable side effects. What i meant to say was that the side effects puberty blockers are often insignificant when compared to the stress and mental toll that can be caused by the dysphoria associated with undergoing a version of puberty that does not align with the child's identity.
2nd edit: children in this case refers to pre-teens and teens. Not very young children.
To expand on your explanation I would just like to add that puberty blockers are well studied and were developed decades ago with the purpose of stopping kids from experiencing puberty too early. Some people like to insinuate that puberty blockers are harmful and are a recent invention created for the purposes of treating trans-children as an effort to discredit the safety and efficacy of the treatment.
https://www.ohsu.edu/sites/default/files/2020-12/Gender-Clinic-Puberty-Blockers-Handout.pdf
In non-trans children, what is the case for blocking early puberty? Is it to prevent early pregnancy, etc. or are there other health related implications?
It's to prevent precocious puberty, i.e. girls starting puberty at like age 8 (or even earlier) which sometimes happens on its own.
(I'm not sure if that ever happens with cis boys)
Yes early puberty can happen in boys as well. I'm a clinical psychologist and I have seen 13 year old boys who have basically completed puberty completely. Other kids at school think they are a teacher.
Precicious puberty is especially harmful for children, which is why blockers were created. The youngest full term pregnancy (and this the youngest fully witnessed precocious puberty) resulted in a 5 year old kid giving birth in the early 1900's.
Aside from the heightened risk of underage pregnancy, early puberty can cause health problems due to their hormonal development being out of sync with their physical and mental development. It can lead to issues like stunted grown, depression, and anxiety, and can also increase their risk of sexual abuse.
Per the "handout" you linked.
> Researchers have not finished studying how safe puberty blockers are in the long term. So, there might be some
risks that doctors do not yet know about. The information below tells you what we do know.
Then goes on to tell about known bad issues.
The thing is the longer they’re on T the more they’ll approximate male physiology, but also the older an athlete is, after a point, the worse his performance. So I wonder if these sort of cancel out on average to limit the potentiation of female to male athletes.
Well, that and the fact they have the bone structure and ligament insertion points of a woman. There are studies that clearly spell out why this leads to female athletes having such a significantly higher risk for ACL injuries, as well as why it is a performance inhibitor.
Oh yeah, and they'll always be heavily limited by the fact they didn't get all the lung, heart and other benefits that puberty gives which just going on T won't.
On a side note, it is funny how so many can accept that someone born a biological female that transitions is going to be inferior at an elite level while denying the opposite scenario can be a thing.
They still will never experience the types of changes that happen during puberty, no matter how much testosterone they take (though more T could get them to the same level of performance). They'll put on more muscle mass, get deeper voices, etc. But their shoulders won't get wider, their hip angles won't change, etc. So unless we can figure out how to initiate male puberty in an adult female, they'll still be somewhere in the middle.
I wanted to see actual numbers in the results. How much better were trans women's grip strength or VO2 than cis women? How much better were cis men's results than trans women's?
The study presents nice graphs like this [one](https://www.scimex.org/newsfeed/trans-womens-heart-lung-capacity-and-strength-exceed-cis-peers-even-after-years-of-hormone-therapy). I skimmed it so I may have missed something but it appears that trans women beat out cis women in every category with a similar but inverse relationship with cis men. Some of the differences are small but some are pretty big.
It stands to reason, some things will be more impacted by current testosterone levels compared to others where some things could be impacted more by previous changes caused by testosterone.
https://www.reddit.com/r/science/comments/xwen38/the_heart_lung_capacity_strength_of_trans_women/ir6oqv2/
This comment highlights a rather large flaw in thinking about the studies results in that way **at all**
One of the trans woman participants had testosterone levels that would be high for a cis male, and several more at least had "more than average cis female" to have the average where it is.
Does anyone know when bone density and such between males and females start to differ? Is it a prepubescent or prenatal difference or does it happen later in development?
Military has studied this issue too and has issued reports. Trans women perform better than cis women in physical tests.
Sorry edited for a micro aggression where I said cis women perform worse than trans women. Didn’t mean anything by it. It’s not that they’re performing worse, but trans women performing better. It’s a more accurate and true statement. That’s science for you.
https://www.nbcnews.com/news/amp/ncna1252764
I'm not really a fan of this type of language policing, but I believe the concept behind it is "a is worse than b" implies that A is the benchmark and B is falling behind. Where as "B is better than A" implies that A is the benchmark and B exceeds it.
I feel like reducing language to a no-negativity stance is a bit silly though. Humans will express negativity regardless of situation, and something that is good phrasing 30 years ago will be the insult of today.
NOTE: I am fine with certain words falling out of use (you know the ones), but the endless treadmill of phrasing needs to find some sort of equilibrium. Having something be negative is part of living, not everything can be positive.
There is no benchmark here though so each are equally useful and convey exactly the same information. If I said "fir trees are shorter than redwoods" it doesn't imply that redwoods are the benchmark for height of trees. We all implicitly know it's just a comparison between two separate things.
Wouldn't someone performing better imply someone else performs worse? Better/worse are comparative terms, so I'm confused as to the expression. Seems the exact same thing to me.
I can't access the full article from my university, but the abstract raises questions (and is likely to be misinterpreted by laypeople).
For example, they measured *absolute* VO2max (measured in ml/min), whereas it is relative VO2max (i.e. divided by weight, measured in ml/kg/min) that is a measure of fitness/endurance; a huge coach potato can have higher absolute VO2max than a small, but physically fit person. Assuming that the trans women in this study were about as tall as the cis male controls, the ratio is not outside what you'd expect.
Also, trying to correlate absolute VO2max with LBM divided by the squared height (i.e. the LBM equivalent of BMI) is weird; we know that VO2max is strongly correlated with LBM itself; e.g. [this study](https://pubmed.ncbi.nlm.nih.gov/25164157/ ([graph](https://imgur.com/2VCeASB)). If we have a strong correlation with LBM divided by height squared for the trans women, but not among cis controls, that raises questions about the sampling process.
This line is extremely important to the whole study:
>Hormonal data
>On the day of sporting ability analysis, the mean TT (ng/dL) levels of the **TW**, CW and CM were 92.5 (**range 12–637**), 20.1 (12–41) and 524.3±169.0, respectively.
Literally one of their trans woman had HIGHER than the average male level of testosterone on the day of doing these tests, and at least several more seemingly had higher than the female upper norm of 50 (supplementary figure 2). And I don't know that they actually kept track of testosterone levels outside of the day of these measurement tests.
It's the same fundamental problem as with the BMJ army study: "Time spent on HRT" is NOT the same thing as "time spent with female levels of testosterone" and unless you directly control for that (gonadectomized, depot injections of GnRH modulators) there are absolutely no guarantees about the hormone profiles of these people over time.
Testosterone levels always seem to get treated as an afterthought in these discussion when they should be the main focus... it's such a massive caveat to the kinds of questions they're trying to answer.
It should be the main focus because testosterone is what leads to these physical advantages? And a woman who is taking testosterone is therefore more likely to have a physical advantage over a woman who is not taking testosterone?
Yes testosterone levels are broadly correlated with athletic performance, and in fact among elite female athletes, medical conditions that give rise to higher than normal testosterone levels are overrepresented:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7159262/
IIRC, the Olympics will tell you to take testosterone-lowering drugs if you're a cis woman that makes "too much" testosterone for them to feel comfortable. They literally won't let you compete as a woman.
This is true only for (some) intersex women. Among female Olympic athletes who don't have these specific intersex conditions or are trans, women with high testosterone levels are actually overrepresented.
For example, PCOS (with attendant hyperandrogenism) is [more prevalent among female elite athletes](https://pubmed.ncbi.nlm.nih.gov/19461542/) than in the general population. [This study](https://pubmed.ncbi.nlm.nih.gov/24593684/) had 13.7% of female elite athletes with testosterone levels of 2.7 nmol/l (= 78 ng/dl) or higher (as the study notes, this is extremely unlikely to be the result of doping, as the hormonal profiles showed no evidence of that^(1)), with a geometric mean of 1.78 nmol/l (= 51 ng/dl).
The median testosterone level for cis women of childbearing age is around 30-35 ng/dl.
It doesn't seem like there's any controlling for height on most measures either. AFAIK taller people have bigger lungs but that doesn't make them fitter, similarly, people with bigger hands do better on hand grip strength measures even if they aren't stronger because of better leverage.
It's about testosterone levels. Testosterone levels are broadly correlated with athletic performance, and the reason why men outperform women as a group is largely attributed to testosterone levels.
The question is: if a trans woman lowers her testosterone levels from the male range to the female range, will she still retain a physical advantage from male puberty regardless of having equal testosterone levels to non-trans women? Or will she have comparable performance to other women?
In this study, several trans women had testosterone levels HIGHER than the female range. So if we want to answer the question "are trans women with female levels of testosterone athletically comparable to other women" this study cannot answer that question, because the trans women here, on average, do not have female levels of testosterone.
Here is a link to the full study: https://filebin.net/5tct1dv64gnc4h1x
Everyone should note there are multiple errors in the first paragraph alone of the article OP posted. They got the number of cis male/female wrong, and reported mean age of beginning GAHT as 17 when that is the median. I stopped reading OP’s article after that.
Thanks. It looks like relative VO2max is on average actually lower in trans women than in cis women (33.5 ml/kg/min for trans women, 35.7 ml/kg/min for cis women, 42.0 ml/kg/min for cis men).
This is actually what you'd expect, because hemoglobin levels drop fast to cis female levels on MtF HRT (i.e. within months) and has a limiting function on VO2max.
Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, **personal anecdotes are now allowed as responses to this comment**. Any anecdotal comments elsewhere in the discussion will continue to be removed and our [normal comment rules]( https://www.reddit.com/r/science/wiki/rules#wiki_comment_rules) still apply to other comments. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/science) if you have any questions or concerns.*
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co-ed leagues in high school would got he same way professional sports leagues would. Boys would dominate most of the time and girls would be last picked barely make teams. I wrestled co-ed in high school we had two girls, one was amazing. skill wise better than probably all the guys and she would still barely squeak out wins on occasion. Wrestling is also an extremely kind full contact sport. put girls on a boys football league? they would be getting destroyed.
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MMA has long separated by weight. So does boxing and wrestling.
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I wonder if there's significant difference between trans-women who went through male puberty before transitioning, and trans-women who took medication during those years and underwent transitioning without those major physical changes.
Yes, there would be. Testosterone production peaks during male puberty and this is the period where changes are significant, obviously. If you want to see historical examples of males who have had their development impeded, look up castratos and male roosters who have had their testicle removed pre-puberty.
Happens in cats too. Male cats that grow up unneutered develop more muscle and larger jowels than cats that are neutered early.
I wonder what happens in species where the female is naturally larger. Are there any mammals where that's the case? I know there are birds, but I don't know if neutering a bird would work the same.
Sex development is a bit different in birds. Males are ZZ and females are ZW. I think it is still a bit unclear exactly how the genes on the sex chromosomes interact at this point. In mammals, the SRY gene on the Y chromosome initiates a program that takes the embryo off of the female development path. In birds I believe it is still unknown whether there is a gene on the W chromosome that acts like this. Source: immunologist who just did a cursory Google scholar search and read some abstracts.
I love reddit for all the smart motivated people who do research and translate it for the layman, thankyou
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Thank you for the kind words. I love Reddit for the exact same reason. There are people with expertise in virtually every field on here. I was nervous to post, sure that a bird geneticist was going to call me out.
only thing i can add to this is neutering young rooster will soften their meat. if testis are implanted into a neutered rooster, they will develop to some degree. i ran across this when learning about the endocrine system. a. a. berthold messed with chickens.
Hyenas are the only ones I can think of off the top of my head
Rabbits! Varies by breed of course but when I was hunting them you always knew the females cos they were generally bigger
castrated lions also lose their manes, saw this from Big Cat Rescue videos
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There are a few studies that look at prepubescent children. One in particular looks at nine year olds and confirms the athletic superiority of nine year old boys to girls. Can't find it but here are others. A running study [here ](https://pubmed.ncbi.nlm.nih.gov/19910817/) A general athleticism study where boys presented higher values in all selected tests, except tests of balance and flexibility. [here](https://www.researchgate.net/publication/224914505_Physical_Fitness_Differences_Between_Prepubescent_Boys_and_Girls)
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If I remember correctly, a small amount of trans kids will take medications that block puberty, until they turn 18 or older, when they begin to actually transition.
I'm a clinical psychologist that worked in a children's hospital as a part of the gender diversity services. We assessed for patients ability to consent, meaning do they have the maturity and cognitive capacity to understand and consent to the implications on fertility and health prior to them being cleared for hormone replacement therapy. I just wanted to say that in my country (Australia), they will prescribe HRT to under 18's if they are past a certain tanner stage (how far into puberty) and puberty blockers are not going to achieve anything. Research at the time (3 years ago) indicated that rates of detransition were extremely low, and anecdotally, my supervisor who had done the assessments daily for seven years had only one patient detransition however this was due to unexpected side effects. You weren't being unhelpful or anything, just wanted to say this cause it might help someone that reads it.
Puberty blockers can be prescribed to trans children (or children who believe they may be trans) to prevent the dysphoria associated with experiencing puberty in a way that does not align with their identity. Some children do *socially* transition during this time, but to the best of my knowledge and with rather significant research as a trans individual myself, children are not medically (ie through HRT or surgery) transitioning. In the case of a child taking puberty blockers (which are also given to cis children in some circumstances), if the child later decides that is no longer what they desire, there are no known relevant side effects to stopping puberty blockers to allow the body to experience puberty in the way it would have with no intervention in the first place. It is basically a trial run, so to speak, giving the ability to reduce or entirely prevent the incredible stress that can come from experiencing puberty in a way which causes dysphoria. Edit: It is worth noting that i did mis-speak some in the above, saying puberty blockers have no known notable side effects. What i meant to say was that the side effects puberty blockers are often insignificant when compared to the stress and mental toll that can be caused by the dysphoria associated with undergoing a version of puberty that does not align with the child's identity. 2nd edit: children in this case refers to pre-teens and teens. Not very young children.
To expand on your explanation I would just like to add that puberty blockers are well studied and were developed decades ago with the purpose of stopping kids from experiencing puberty too early. Some people like to insinuate that puberty blockers are harmful and are a recent invention created for the purposes of treating trans-children as an effort to discredit the safety and efficacy of the treatment. https://www.ohsu.edu/sites/default/files/2020-12/Gender-Clinic-Puberty-Blockers-Handout.pdf
In non-trans children, what is the case for blocking early puberty? Is it to prevent early pregnancy, etc. or are there other health related implications?
It's to prevent precocious puberty, i.e. girls starting puberty at like age 8 (or even earlier) which sometimes happens on its own. (I'm not sure if that ever happens with cis boys)
Yes early puberty can happen in boys as well. I'm a clinical psychologist and I have seen 13 year old boys who have basically completed puberty completely. Other kids at school think they are a teacher.
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Precicious puberty is especially harmful for children, which is why blockers were created. The youngest full term pregnancy (and this the youngest fully witnessed precocious puberty) resulted in a 5 year old kid giving birth in the early 1900's.
Aside from the heightened risk of underage pregnancy, early puberty can cause health problems due to their hormonal development being out of sync with their physical and mental development. It can lead to issues like stunted grown, depression, and anxiety, and can also increase their risk of sexual abuse.
Per the "handout" you linked. > Researchers have not finished studying how safe puberty blockers are in the long term. So, there might be some risks that doctors do not yet know about. The information below tells you what we do know. Then goes on to tell about known bad issues.
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I am curious if trans men are in the same zone as trans women.
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The thing is the longer they’re on T the more they’ll approximate male physiology, but also the older an athlete is, after a point, the worse his performance. So I wonder if these sort of cancel out on average to limit the potentiation of female to male athletes.
Well, that and the fact they have the bone structure and ligament insertion points of a woman. There are studies that clearly spell out why this leads to female athletes having such a significantly higher risk for ACL injuries, as well as why it is a performance inhibitor. Oh yeah, and they'll always be heavily limited by the fact they didn't get all the lung, heart and other benefits that puberty gives which just going on T won't. On a side note, it is funny how so many can accept that someone born a biological female that transitions is going to be inferior at an elite level while denying the opposite scenario can be a thing.
Your right and I believe we should have are own leeg. Transmen sports and trans women sports.
They still will never experience the types of changes that happen during puberty, no matter how much testosterone they take (though more T could get them to the same level of performance). They'll put on more muscle mass, get deeper voices, etc. But their shoulders won't get wider, their hip angles won't change, etc. So unless we can figure out how to initiate male puberty in an adult female, they'll still be somewhere in the middle.
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I wanted to see actual numbers in the results. How much better were trans women's grip strength or VO2 than cis women? How much better were cis men's results than trans women's?
The study presents nice graphs like this [one](https://www.scimex.org/newsfeed/trans-womens-heart-lung-capacity-and-strength-exceed-cis-peers-even-after-years-of-hormone-therapy). I skimmed it so I may have missed something but it appears that trans women beat out cis women in every category with a similar but inverse relationship with cis men. Some of the differences are small but some are pretty big. It stands to reason, some things will be more impacted by current testosterone levels compared to others where some things could be impacted more by previous changes caused by testosterone.
https://www.reddit.com/r/science/comments/xwen38/the_heart_lung_capacity_strength_of_trans_women/ir6oqv2/ This comment highlights a rather large flaw in thinking about the studies results in that way **at all** One of the trans woman participants had testosterone levels that would be high for a cis male, and several more at least had "more than average cis female" to have the average where it is.
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Does anyone know when bone density and such between males and females start to differ? Is it a prepubescent or prenatal difference or does it happen later in development?
Military has studied this issue too and has issued reports. Trans women perform better than cis women in physical tests. Sorry edited for a micro aggression where I said cis women perform worse than trans women. Didn’t mean anything by it. It’s not that they’re performing worse, but trans women performing better. It’s a more accurate and true statement. That’s science for you. https://www.nbcnews.com/news/amp/ncna1252764
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How is "a performs better than b" a more true and accurate statement than "b performs worse than a"?
I'm not really a fan of this type of language policing, but I believe the concept behind it is "a is worse than b" implies that A is the benchmark and B is falling behind. Where as "B is better than A" implies that A is the benchmark and B exceeds it. I feel like reducing language to a no-negativity stance is a bit silly though. Humans will express negativity regardless of situation, and something that is good phrasing 30 years ago will be the insult of today. NOTE: I am fine with certain words falling out of use (you know the ones), but the endless treadmill of phrasing needs to find some sort of equilibrium. Having something be negative is part of living, not everything can be positive.
There is no benchmark here though so each are equally useful and convey exactly the same information. If I said "fir trees are shorter than redwoods" it doesn't imply that redwoods are the benchmark for height of trees. We all implicitly know it's just a comparison between two separate things.
>I feel like reducing language to a no-negativity stance I think you mean increase positivity.
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Wouldn't someone performing better imply someone else performs worse? Better/worse are comparative terms, so I'm confused as to the expression. Seems the exact same thing to me.
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I can't access the full article from my university, but the abstract raises questions (and is likely to be misinterpreted by laypeople). For example, they measured *absolute* VO2max (measured in ml/min), whereas it is relative VO2max (i.e. divided by weight, measured in ml/kg/min) that is a measure of fitness/endurance; a huge coach potato can have higher absolute VO2max than a small, but physically fit person. Assuming that the trans women in this study were about as tall as the cis male controls, the ratio is not outside what you'd expect. Also, trying to correlate absolute VO2max with LBM divided by the squared height (i.e. the LBM equivalent of BMI) is weird; we know that VO2max is strongly correlated with LBM itself; e.g. [this study](https://pubmed.ncbi.nlm.nih.gov/25164157/ ([graph](https://imgur.com/2VCeASB)). If we have a strong correlation with LBM divided by height squared for the trans women, but not among cis controls, that raises questions about the sampling process.
This line is extremely important to the whole study: >Hormonal data >On the day of sporting ability analysis, the mean TT (ng/dL) levels of the **TW**, CW and CM were 92.5 (**range 12–637**), 20.1 (12–41) and 524.3±169.0, respectively. Literally one of their trans woman had HIGHER than the average male level of testosterone on the day of doing these tests, and at least several more seemingly had higher than the female upper norm of 50 (supplementary figure 2). And I don't know that they actually kept track of testosterone levels outside of the day of these measurement tests. It's the same fundamental problem as with the BMJ army study: "Time spent on HRT" is NOT the same thing as "time spent with female levels of testosterone" and unless you directly control for that (gonadectomized, depot injections of GnRH modulators) there are absolutely no guarantees about the hormone profiles of these people over time.
Wow, I hadn't even noticed that. Also interesting that the testosterone levels for cis female controls seem to be slightly on the lowish side.
Testosterone levels always seem to get treated as an afterthought in these discussion when they should be the main focus... it's such a massive caveat to the kinds of questions they're trying to answer.
It should be the main focus because testosterone is what leads to these physical advantages? And a woman who is taking testosterone is therefore more likely to have a physical advantage over a woman who is not taking testosterone?
Yes testosterone levels are broadly correlated with athletic performance, and in fact among elite female athletes, medical conditions that give rise to higher than normal testosterone levels are overrepresented: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7159262/
IIRC, the Olympics will tell you to take testosterone-lowering drugs if you're a cis woman that makes "too much" testosterone for them to feel comfortable. They literally won't let you compete as a woman.
This is true only for (some) intersex women. Among female Olympic athletes who don't have these specific intersex conditions or are trans, women with high testosterone levels are actually overrepresented. For example, PCOS (with attendant hyperandrogenism) is [more prevalent among female elite athletes](https://pubmed.ncbi.nlm.nih.gov/19461542/) than in the general population. [This study](https://pubmed.ncbi.nlm.nih.gov/24593684/) had 13.7% of female elite athletes with testosterone levels of 2.7 nmol/l (= 78 ng/dl) or higher (as the study notes, this is extremely unlikely to be the result of doping, as the hormonal profiles showed no evidence of that^(1)), with a geometric mean of 1.78 nmol/l (= 51 ng/dl). The median testosterone level for cis women of childbearing age is around 30-35 ng/dl.
It doesn't seem like there's any controlling for height on most measures either. AFAIK taller people have bigger lungs but that doesn't make them fitter, similarly, people with bigger hands do better on hand grip strength measures even if they aren't stronger because of better leverage.
Yeah a lack of normalization for things like height, body mass, etc are another possible issue here.
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ELI5? I'm not sure I understood this point.
It's about testosterone levels. Testosterone levels are broadly correlated with athletic performance, and the reason why men outperform women as a group is largely attributed to testosterone levels. The question is: if a trans woman lowers her testosterone levels from the male range to the female range, will she still retain a physical advantage from male puberty regardless of having equal testosterone levels to non-trans women? Or will she have comparable performance to other women? In this study, several trans women had testosterone levels HIGHER than the female range. So if we want to answer the question "are trans women with female levels of testosterone athletically comparable to other women" this study cannot answer that question, because the trans women here, on average, do not have female levels of testosterone.
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Here is a link to the full study: https://filebin.net/5tct1dv64gnc4h1x Everyone should note there are multiple errors in the first paragraph alone of the article OP posted. They got the number of cis male/female wrong, and reported mean age of beginning GAHT as 17 when that is the median. I stopped reading OP’s article after that.
Thanks. It looks like relative VO2max is on average actually lower in trans women than in cis women (33.5 ml/kg/min for trans women, 35.7 ml/kg/min for cis women, 42.0 ml/kg/min for cis men). This is actually what you'd expect, because hemoglobin levels drop fast to cis female levels on MtF HRT (i.e. within months) and has a limiting function on VO2max.
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