By continuing to argue that female sports must be a category restricted to females?
Here is the @WomensSportsFdn policy on inclusion of transwomen in female sports. No idea which medical experts or data they are referencing. 
I wonder if @WomensSportsFdn and @BillieJeanKing have seen the latest data from the Karolinska?
academic.oup.com/jcem/advance-a…
academic.oup.com/jcem/advance-a…
A reminder of their findings.
After 12 months of hormone therapy (the threshold set by most sporting bodies), transwomen lost minimal muscle mass and strength was maintained.
After 12 months of hormone therapy (the threshold set by most sporting bodies), transwomen lost minimal muscle mass and strength was maintained.
There is other muscle/strength data that can be mined from:
Gooren and Bunck 2004
Haraldsen et al 2007
Lapauw et al 2008
Van Caenegem et al 2015
Klaver et al 2018
The last gives a handy picture. Not much going on with lean body mass there.
Gooren and Bunck 2004
Haraldsen et al 2007
Lapauw et al 2008
Van Caenegem et al 2015
Klaver et al 2018
The last gives a handy picture. Not much going on with lean body mass there.
Males have around 40% more muscle mass at baseline. Losing 5% after 12 months of hormone treatment is hardly ‘negating muscle advantage’.
The changes in fat appear far more extensive, but males have much lower body fat to start with. If your baseline is 15% (‘fit man’), +25% brings you to about 18%. This is still thinner than ‘fit women’ references.
And of course, little reason to think transitioning males athletes will see the same increase in body fat.
