We recently posted an article on the subject of trans inclusion in sport, particularly the issue of trans women in sport.  This has always been a contentious matter, most notably with the public and the media as seen from recent press, televised debates and comment pages.  Unfortunately many of these merely report opinion.  Many of us have read the comments the public make regarding “biology” and “immutable advantages” and the perceived “fairness” of Assigned Male at Birth (AMAB) people competing in women’s competition.  Taking the particularly hostile comments aside, what can we expect from a public not shown the facts?  What is required is not debate, not discussion of existence and right to choose one’s identity, not opinion, but presentation of the facts.  My right to identity and how I and others choose to express that is not open for debate, it just is.  However, is it “fair” if I, or indeed somebody much better than me at a chosen sport participate in a gendered competition with other women?  Physiologically, after a year on hormone replacement therapy (HRT), yes it is fair.

This article is not going to dispute that there are general differences in the physicality of men and women.  Many texts can be found on differences in muscle mass, cardiac function, lung capacity, skeletal construction etc.  However, many of these differences exist because of testosterone and only remain in the continued presence of testosterone as it is an anabolic steroid.  Indeed, many athletes have taken testosterone as a performance enhancing drug to benefit from these effects mentioned.  As a result testosterone and other anabolic androgenic steroids are banned substances.

So, does an athlete found to have been taking testosterone have a lifelong advantage over one who has not? A look at the USADA report on sanctions imposed upon athletes caught with high testosterone from doping shows a fairly consistent time of suspension, 12 months – 2 years (with the exception of Lance Armstrong who got a lifetime ban for trafficking and administering to others).  The decisions made by the authorities on these matters take into account the lasting effects of substances taken, coupled with a punitive term.  If the effects of testosterone on muscle and cardiovascular function were permanent, then shouldn’t any athlete caught taking it be banned for life?  The simple answer is the effects of testosterone only last a short time (several months) without the continued presence of it.

Trans men are given advice regarding testosterone supplementation and what effects are likely to remain should he/they stop taking it.  Of key note is that muscle and fat changes “will revert to more female patterns” more obvious if the ovaries are still present, i.e. there is an oestrogen influence.  A trans woman will be on oestrogen as part of a standard HRT regimen effectively creating pharmacological ovaries.  So, a trans woman pre-transition could be likened to a female athlete on testosterone supplementation for performance enhancement.  She has the athletic benefit of greater muscle mass (fibre number is genetically predetermined – size of those fibres is due to anabolic factors like testosterone), greater cardiovascular performance and in some cases an advantageous skeletal structure.  During transition she has her testosterone blocked (cyproterone, spironolactone and decapeptyl are common blockers affecting production and response to any remaining testosterone) and takes oestrogen for 12 months according to the IOC guidelines satisfying the conditions that any athlete on testosterone legitimate or otherwise would have placed upon them.  The guidelines for trans women state that “total testosterone level in serum has been below 10 nmol/L for at least 12 months”, in place of the original requirement to be 2 years post gender reassignment surgery.

So what happens in that 12 month period that satisfies 20 medical and legal professionals?  Without the continued anabolic effect of testosterone, the muscles begin to atrophy (decrease in size and mass).  As I mentioned above the fibre number does not change, but the size of those fibres does.  This is due to the ongoing breaking down and rebuilding process the body engages in, general wear and tear from everyday life and various healing and repair mechanisms.  Without testosterone, this process is slower with a lower balance point in general.  A more extreme example would be an astronaut returning to earth’s gravity.  Due to reduced use of the muscles in microgravity the muscles atrophy.

I am using generalisations here.  When assessing averages we must remember there is a significant spread either side of the average in a bell-shaped curve.  The bell curves of men and women do overlap!  Below is an example bell curve distribution displaying height in a sample of American individuals.  Bell curves for other parameters in different ethnicities are very similar.

Male and female averages differ, but the distribution around that average can be closer than you think

Male and female averages differ, but the distribution around that average can be closer than you think

The cardiovascular capacity will reduce to typically female ranges.  There have been some interesting scientific studies assessing the hormonal and genetic basis in cardiovascular performance showing that the sex differences are predominantly hormonal i.e. apparent only with testosterone present and working.   Skeletally, the bone density will adopt a more female pattern too.  The only thing that is very difficult to alter would be the skeletal structure itself.

But this is where it is important to consider the bell curve distribution again.  Men and women are different by averages and you will often see extreme examples of differences .  We must be careful to consider the selection of these images and case studies.  If you compare a male basketball player with a female gymnast you are not comparing like with like.  A female basketball player is not going to resemble a female gymnast physically either! Should an athlete transition, it is very unlikely they will compete in a completely different sport.  Once again the bell curves show much overlap, so a female basketball player will look and perform much more like a male basketball player than a female gymnast.

So the answer to the question of, “Is it fair for trans women to compete with other women?” is yes.  The IOC and the experts it consulted, along with my own personal knowledge of physiology says that any advantage a man may have over a woman is due to the effects of testosterone that wear off once that testosterone is no longer present.

So far this article has addressed the binary question of trans women in women’s sport (there are no rules preventing trans men competing in men’s sport).  What I have not addressed is non-binary inclusion.  For an AFAB (Assigned Female at Birth) non-binary person, they may compete in women’s competition if no testosterone has been taken or compete in men’s competition if any testosterone has been taken.  For an AMAB non-binary person, they may compete in men’s competition or, as discussed in this article, compete in women’s competition once the testosterone level requirements are met.  However, competing in categories one doesn’t necessarily identify with can be potentially distressing.  Given that there is much more overlap between men and women that many people realise, is the segregation of men and women the best means of separating competition for fairness?  A thought to consider, is there really that much difference between male and female competition?  Women’s sport is of a much higher calibre than most people give credit for.  Could we not move to a system of “classes” much like weight classes in martial arts?  People of similar ability compete with one another regardless of gender identity or expression with no significant impact on the fairness of competition.  In fact, competing in groups of similar ability would make for close contests, fun to participate in and entertaining to watch.

Until that time we do have gender segregation for sport, so let a woman compete as a woman.

Charlotte S. McCarroll (@TransCharlotte)