Since I doubt OP will be returning, and we have lots of new posters, I am going to post the evidence that relates specifically to sport. However, this evidence is also entirely relevant for the discussion about why male people at any stage of transition or not, should not be accessing any female single sex space.
I hope that when I have posted these links and people take the time to read them, that people will no longer feel that 'sports is a grey area'. Because it is NOT a grey area, the harms are very clear once you see it laid out. The harms are hidden behind what is effectively a demand to 'be kind' though. Even the fucking IOC has doubled down that male feelings should be prioritised above female athlete safety and fairness.
Here is an excellent summary of the current situation and why this is not a 'grey area'.
https://onlinelibrary.wiley.com/doi/epdf/10.1111/sms.14581
Tommy R. Lundberg, Ross Tucker, Kerry McGawley, Alun G. Williams, Grégoire P. Millet, Øyvind Sandbakk, Glyn Howatson, Gregory A. Brown, Lara A. Carlson, Sarah Chantler, Mark A. Chen, Shane M. Heffernan, Neil Heron, Christopher Kirk, Marie H. Murphy, Noel Pollock, Jamie Pringle, Andrew Richardson, Jordan Santos-Concejero, Georgina K. Stebbings, Ask Vest Christiansen, Stuart M. Phillips, Cathy Devine, Carwyn Jones, Jon Pike, Emma N. Hilton
Perspectives:
The IOC framework on fairness, inclusion and nondiscrimination on the basis of gender identity and sex variations is misaligned with current scientific and medical evidence and offers insufficient protection of fair competition for female athletes within a female category. Also, it does not adequately engage female athletes, who are primary stakeholders in their sport. Male pubertal development results in large performance advantages in athletic sports, which necessitates a female category that excludes male advantages, to ensure equal opportunity through fair competition for female athletes at all levels of sport. There is currently no evidence that testosterone suppression in transgender women can reverse male development and negate male advantages. In contrast, there is convincing evidence that the male advantage persists even when testosterone is suppressed. As a result, sports face the uncomfortable reality that the inclusion of transgender women in female sports categories cannot be reconciled with fairness, and in some instances safety, for females in athletic sports. The IOC must reconsider its framework and revise the 10 principles to reflect scientific evidence and fundamental principles of fair competition. We also recommend implementing a system to enable female stakeholders to be consulted in this matter and to have their voices heard, recognized, and valued.
I would suggest starting with these two reviews for further research.
This one from Dr Hilton and T Lundberg. is the source for the graphic I have attached below.
https://link.springer.com/article/10.1007/s40279-020-01389-3
Harper et al.
bjsm.bmj.com/content/early/2021/02/28/bjsports-2020-103106
Conclusions are in line with No. 1. For information (considering many people will seek to discredit based on alleged bias) Harper is the transwoman who has released some sports studies in the past that had some methodology issues.
Here is the USAF study here for people to read.
bjsm.bmj.com/content/early/2020/11/06/bjsports-2020-102329
Timothy A Roberts, Joshua Smalley, Dale Ahrendt
Effect of gender affirming hormones on athletic performance in transwomen and transmen: implications for sporting organisations and legislators
Summary The 15–31% athletic advantage that transwomen displayed over their female counterparts prior to starting gender affirming hormones declined with feminising therapy. However, transwomen still had a 9% faster mean run speed after the 1 year period of testosterone suppression that is recommended by World Athletics for inclusion in women’s events.
It is interesting reading as it also leaves the suggestion that even after 3 years advantage still exists.
And Sean Ingle’s take on it.
www.theguardian.com/sport/2020/dec/07/study-suggests-ioc-adjustment-period-for-trans-women-may-be-too-short
Another study, this time the Brazilian study:
The Brazilian study.
bjsm.bmj.com/content/early/2022/09/01/bjsports-2021-105400.info
Cardiopulmonary capacity and muscle strength in transgender women on long-term gender-affirming hormone therapy: a cross-sectional study
Leonardo Azevedo Mobilia Alvares, Marcelo Rodrigues Santos, Francis Ribeiro Souza, Lívia Marcela Santos, Berenice Bilharinho de Mendonça, Elaine Maria Frade Costa, Maria Janieire Nazaré Nunes Alves, Sorahia Domenice
This is the conclusion:
Conclusion
In this small cohort of non-athlete TW, who were previously exposed to male pubertal development and underwent long-term oestrogen therapy, we identified higher grip strength and VO2 peak levels than in non-athlete CW, but these same parameters were lower compared with non-athlete CM.
These findings add new insights to the sparse information available on a highly controversial topic about the participation of TW in physical activities. Future studies involving transgender athletes that account for and quantify variable exposure times to pubertal development and assess muscle cell metabolism are needed to elucidate the effects of long-term GAHT on TW sports performance.
From Ross Tucker, an expert sport scientist on this study above:
Over a decade (14.4 yrs average) of T-suppression, and TW have VO2max 20% higher, grip strength 19% higher & skeletal mass 40% than women. More evidence that male biology persists long after T is removed. Another piece of the same puzzle, albeit from a cross-sectional study.
The cross-sectional bit is important - the study hasn't (like over a dozen others) tracked people from Day zero onwards, so the differences are a 'snapshot' rather than a 'movie', if that makes sense? Means you don't know how those TW began, 14.4 yrs earlier, but the finding of quite large differences compared to women (20% or more) is striking, because a) they either began as typically representative of males, and lost some, but retained significant advantages vs women, or b) they began well below men, and lost hardly any advantages. In either case, the end point, over a decade later, is biological differences compared to women that will create performance implications. Of interest, the mass retention and VO2max advantage mean that relative VO2max (ml/kg/min) ends up similar, which means in some sports (weight-determined) the performance implication may differ - sometimes very large, sometimes smaller, as in some categories within endurance sports.
But zero? Unlikely, because cardio function, FFM & strength are greater. Important paper, showing striking biological 'persistence' 14 yrs on.
Two further thoughts on the study. First, the TW vs women differences in muscle mass and strength remain large (20%) after more than a decade of T suppression. One year vs ten, biology "persists". Second, add training to the mix and TW and women would obviously get stronger.
You could TRY to argue that women would get stronger relatively more than TW (you'd have a job on your hands to explain why this would be, but anyway). More likely is that the differences - TW vs women - would persist or even increase with the addition of training. What this study confirms is that non-trained TW retain biological differences with performance implications after 14 years of T suppression. You'd have to believe that W could make up these gaps with training to believe in fairness in sport. That is, trained W = non-trained TW = fair!
Here is a study released 14th December 2022 from Nederlands and Denmark about the physical impact of reduction of testostorone on performance of male athletes.
pubmed.ncbi.nlm.nih.gov/36534950/
Lisanne H P Houben, Maarten Overkamp, Puck van Kraaij, Jorn Trommelen, Joep G H van Roermund, Peter de Vries, Kevin de Laet, Saskia van der Meer, Ulla R Mikkelsen, Lex B Verdijk, Luc J C van Loon, Sandra Beijer, Milou Beelen
Abstract
Purpose: To assess the effects of 20 weeks resistance exercise training with or without protein supplementation on body composition, muscle mass, muscle strength, physical performance and aerobic capacity in prostate cancer patients receiving androgen deprivation therapy (ADT).
Methods: Sixty prostate cancer patients receiving ADT were randomly assigned to perform 20 weeks of resistance exercise training with supplementation of 31 g whey protein (EX+PRO, n = 30) or placebo (EX+PLA, n = 30), consumed immediately after exercise and every night before sleep. A separate control group (CON, n = 36) only received usual care. At baseline and after 20 weeks, body composition (dual energy X-ray absorptiometry), muscle mass (computed tomography scan), muscle strength (1-repetition maximum strength tests), physical performance (Timed Up and Go Test, 30-second Chair Stand Test, Stair Climb Test), aerobic capacity (cardiopulmonary exercise test) and habitual dietary intake (food diary), were assessed. Data were analyzed using a two-factor repeated-measures ANOVA.
Results: Over time, muscle mass and strength increased in EX+PRO and EX+PLA and decreased in CON. Total fat mass and fat percentage increased in EX+PRO and CON, but not in EX+PLA. Physical performance did not significantly change over time in either group. Aerobic capacity was maintained in EX+PLA, while it decreased in EX+PRO and CON. Habitual protein intake (without supplements) averaged >1.0 g·kg body weight-1·day-1, with no differences over time or between groups.
Conclusions: In prostate cancer patients, resistance exercise training counteracts the adverse effects of ADT on body composition, muscle mass, muscle strength and aerobic capacity, with no additional benefits of protein supplementation.
This is an article about the connection of injury with menstrual cycle. It is yet another reason why female people need to be competing with only female people because they are more prone to injury from male bodies. Plus because no male person on this planet has had to deal with the physical consequences of menstrual cycles which means that including them into the sports category discriminates against female people who have had to deal with menstrual cycles disrupting their training and their competition.
https://www.economist.com/science-and-technology/2021/06/24/acl-injuries-are-a-growing-problem
Plug this into archive dot is for the full version.
One of the most curious features of ACL injuries, though, is that they afflict women far more often than men—as much as eight times more, some investigations suggest. Why this might be is the subject of intensive research. But a clue lies in an apparent connection with the menstrual cycle.
A study published in 2013, of a group of women skiers in the Alps, for example, found that those in the pre-ovulatory stage of the cycle were more than twice as likely to suffer an ACL tear than were those in the post-ovulatory stage. A four-year survey of 113 female England footballers, published in March, also found a clear correlation. Muscle and tendon injuries were far more common in the late follicular phase of the cycle, just prior to ovulation, than in the other phases.
The reason for this menstrual-cycle link is unclear. The ACL has oestrogen receptors, which might help to explain what is happening. But it is not unique among ligaments in this, and the receptors’ job is, in any case, obscure. Levels of oestrogen in the body do spike just before ovulation—the point when tear-frequency rises—but uncertainty remains about the exact link.
Other contributory factors to women’s higher ACL tear rate may be female body shapes and movement patterns. Compared with men, women have wider hips, more inverted knees and “over-dominant“ quad muscles (meaning that the quadriceps femoris muscle group in front of the thigh bone is relatively stronger than the hamstring group behind it). All these factors put pressure on the elaborate workings of the knee joint. Women also tend to land in a more flat-footed manner than men do, and to pivot more awkwardly.
This study is for those posters who don't believe that even at six years old that male athletes have physical advantages over female athletes.
Danish study on VO2 max and LBM in children from age 6
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1725036/pdf/v039p00725.pdf
Maximum oxygen uptake and objectively measured physical activity in Danish children 6-7 years of age: the Copenhagen school child intervention study
Eigberg, Hasselstrom, Gronfeldt, Friberg, Svensson, Anderson
October 2005
Objectives: To provide normative data on maximum oxygen uptake (Vo(2)max) and physical activity in children 6-7 years of age and analyse the association between these variables.
Methods: Vo(2)max was measured in 366 boys (mean (SD) 6.8 (0.4) years of age) and 332 girls (6.7 (0.4) years of age) from preschool classes in two suburban communities in Copenhagen, during a progressive treadmill exercise. Habitual physical activity was measured with accelerometers.
Results: Boys had higher Vo(2)max both in absolute values (1.19 (0.18) v 1.06 (0.16) litres/min (+11%), p<0.001) and relative to body weight (48.5 (6.0) v 44.8 (5.6) ml/kg/min (+8%); p<0.001) than girls. The difference in Vo(2)max between boys and girls decreased to +2% when expressed relative to lean body mass (LBM). Absolute Vo(2)max was related to LBM, body mass, and stature (all p<0.001). Boys were more physically active than girls (mean counts +9.4%, p<0.001), and even when boys and girls with the same Vo(2)max were compared, boys were more active. The difference in physical activity between the sexes was higher when sustained activity of higher intensity was compared.
Conclusions: Vo(2)max is higher in boys than girls (+11%), even when related to body mass (+8%) and LBM (+2%). Most of the difference in Vo(2)max relative to body mass was explained by the larger percentage body fat in girls. When boys and girls with the same Vo(2)max were compared, boys engaged in more minutes of exercise of at least moderate intensity.
Plus this study on performance across Australian children
https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=021cccdaed57d120bb05bac71c05ee82b0c5b315
And
New study released on sex differences between male and female children under 11 years old.
Sex-based differences in track running distances of 100, 200, 400, 800, and 1500m in the 8 and under and 9–10-year-old age groups
Gregory A Brown, Brandon S Shaw, Ina Shaw
5th February 2024
https://onlinelibrary.wiley.com/doi/10.1002/ejsc.12075
"In conclusion, although some have stated that sex-based differences in athletic performance do not arise until puberty, the present data indicate that in the 8 and under and 9–10-year-old age groups males run faster than females in distances of 100, 200, 400, 800, and 1500m. While some females in these age groups are faster than some males, the average male finalists are faster than the average female finalists, and the fastest males are faster than the fastest females. As running is a key component of many sports, these sex-based differences between prepubertal males and females should be considered when sport governing bodies and policy makers consider the issue of sex-based sporting categories"
If people prefer to watch a video discussion, here is a good one.
Here is an interesting video led by Prof Jo Phoenix, with Dr Emma Hilton and Jon Pike. OUGCRN Seminar : Sex, Gender, and Sport after Tokyo
As they point out the 69 kg male weightlifting champion at 164 cm can lift more weight and any female weightlifting champion. Even Tatiana Kashirina who is 108 kg an 177 cm tall. She goes through Hubbard's advantages.
It is an interesting seminar particularly for anyone who perhaps wants a summary of sex vs gender or a reminder.
Or this one below
This is quite a good discussion on transitioned males in sport done by Australia's SBS TV channel. It includes people like Jane Fleming (Olympic athletics champ), Deborah Acason (Commonwealth games female weighlifting champion and pioneer), Holly Lawford-Smith, Prof David Handelsman (Uni of Sydney) specialist in Testosterone, Dr Roslyn Carbon (part of the team developing UK Sports guidance), Mianne Baggar and Joanne Harper.
Overall, it showed just how much the inclusive side fall onto emotional manipulation in the face of overwhelming evidence that counters their claims.
I have more. Just ask.
TL/DR
Sport is NOT a 'grey area' if you take the time to read and familiarise yourself with the evidence and the emotionally laden arguments that now are the only remaining option for including male athletes in female sports.
Plus there is NO 'case by case' solution. It has been modelled by countless experts on all sides of the discussion and NO ONE has developed a model that works!
Plus no feminist is saying that trans people should be 'banned' from sport. Male people have other options available to them. A luxury that female athletes simply do not have.