The IAAF Still Can't Spell "Male Puberty"

The International Amateur Athletics Federation has lately released a new version of their eligibility regulations for female classification (PDF, h/t Cathy Young). It is superior to the IOC's eligibility requirements in one respect only: it actually contains references to scientific papers. Particularly, the IAAF document rests on the fulcrum of an October, 2018 Endocrine Reviews paper, "Circulating Testosterone as the Hormonal Basis of Sex Differences In Athletic Performance" by David J Handelsman, Angelica L Hirschberg, and Stephane Bermon. The concluding bullet point of their "Essential Points" section reads (emboldening mine):

Based on the nonoverlapping, bimodal distribution of circulating testosterone concentration (measured by liquid chromatography–mass spectrometry) with 95% references ranges of 7.7 to 29.4 nmol/L in healthy men and 0 to 1.7 nmol/L in healthy premenopausal women—making an allowance for women with the mild hyperandrogenism of polycystic ovary syndrome, who are overrepresented in elite athletics—the eligibility criterion for female athletic events should be a circulating testosterone concentration of <5.0 nmol/L

This of course fails to explain the results from the Karolinska Institute, which showed M2F transsexuals still retained the majority of their muscle mass (PDF) even after testosterone suppression therapy.  Handelsman et al. at least have the good sense to mention male puberty:

The strongest justification for sex classification in elite sports is that after puberty men produce 20 times more testosterone than women (4–7), resulting in circulating testosterone concentrations 15-fold higher than in children or women of any age. Age-grade competitive sporting records show no sex differences prior to puberty, whereas from the age of male puberty onward there is a strong and ongoing male advantage (8). The striking male postpubertal increase in circulating testosterone provides a major, ongoing, cumulative, and durable physical advantage in sporting contests by creating larger and stronger bones, greater muscle mass and strength, and higher circulating hemoglobin as well as possible psychological (behavioral) differences. In concert, these render women, on average, unable to compete effectively against men in power-based or endurance-based sports.

They later have the guts to bust out with an obvious truth: "If sex classification were eliminated [in sporting events], such open or mixed competitions would be dominated almost exclusively by men." But in the end, this is so much lip service. They have no way of explaining the Karolinska results without also taking into account the advantages of undergoing male puberty. It is not enough to suppress testosterone.

Update: Reminder that the IOC knew or should have known that testosterone suppression was inadequate back in 2016 when they cooked up that document. Dr. Antonia Lee last year asked several people involved in the process to comment now that there have been a significant number of M2F transsexuals beating biological women in various athletic events. Particularly interesting is the section on professor Arne Ljungqvist (note, I have added hyperlinks to the footnote):

In 2005 and writing in the Lancet (5), Ljungqvist, in a basic review of the literature commented, “…after one year of therapy, male-to-female muscle mass remained greater than that observed in the comparison female-to-male group…”. In other words, he was previously aware of at least one retained physical advantage as shown in one study that had informed the IOC’s former (2004) and more demanding participation guidelines. In the same Lancet piece, Ljungqvist also says, “Ultimately, the number of transsexual athletes who can successfully compete in open international events is likely to be small, in accord with the estimated incidence of gender dysphoria of one in about every 12 000 men and one in about every 30 000 women”.

The IAAF document looks, in this light, increasingly a product of an engineered process designed to arrive at a conclusion already decided upon.