I am just going to put this on the thread too in anticipation of the 'women have high testosterone too! argument. We can then refer people back to this:
TESTOSTERONE LEVEL CHART - NORMAL FEMALE RANGE / PCOS RANGE / NORMAL MALE RANGE
USING DAVID HANDELSMAN INFORMATION INCLUDING THE LEVELS IOC SPECIFIED FOR TESTOSTERONE SUPPRESSION
This is the chart was made using information from the Handelsman et al 2018 paper below.
The 'Caster Semenya' line refers to what the IOC had specified that Semenya and others needed to suppress their testosterone levels down to, resulting in Semenya trying to overturn this at CAS.
Semenya was noted in that CAS case to have the difference in sex development categorised as 5-ARD and had testosterone levels of around 21 nmol/L.
The Hubbard line was the testosterone level that males with transgender identities had to suppress to for the 2020 Tokyo Olympics.
This is tweet where you can find the chart.
https://x.com/rorybowman/status/1819232725175620084
This is the study
Circulating Testosterone as the Hormonal Basis of Sex Differences in Athletic Performance
David J Handelsman, Angelica L Hirschberg, Stephane Bermon
Published: 13 July 2018
https://academic.oup.com/edrv/article/39/5/803/5052770?login=false
A poster once tried to say that Handelsman obviously supports testosterone reduction, however, this is untrue.
What is important to note here is that David Handelsman has since said this in 2022 on the SBS Insight episode after seeing further research.
“Question: does testosterone suppression get rid of the natural advantage males have?”
“It is important to remember that what we are talking about here is the unfair advantage so the objective is to eliminate it not just reduce it. But complete testosterone suppression has now be shown in a number of studies to not to fully nullify the advantages in males, in physical advantages for up to three years.”
“Suppression of testosterone is partially effective. It won’t change bones. They remain longer and stronger. Haemoglobin will change, but the key things muscle, heart and lungs virtually don’t change. Or they change very little, maybe 10 - 20% reduction. But 80% of the male physical advantage remains . So it is virtually incomplete, and no where near completely reversing male unfair advantage.”
“More on testosterone suppression:”
“The key thing is whether the male physical advantage is removed over a certain time. And the answer is there is no duration which removes the unfair male physical advantage of male bodied athletes in female events. The data shows that you can get some reversal, but no where near complete and therefore there remains an unfair advantage.”