There has been an increasingly prevalent discussion in the wider culture surrounding those who are transgender and their participation in sports. However, much of the noise surrounding the debate has been focused on the inclusion of the trans demographic in sports, with a disturbing lack of discussion around the nuances of the issue. Exploring such a sensitive topic is an unenviable task, especially with the current administration blanket assault on the rights and merit of the transgender and transsexual communities. However, with such a question being posed, we will do our best to answer it using the facts offered by science.

First, let’s explore the difference between transgender and transsexual. Transgenderism is the adoption of the mannerisms, styles, inflections and expressions associated with the opposite sex. Gender is a socially constructed phenomenon; in other words, what one culture considers to be masculine might be associated with femininity in another culture, or vice versa. Transsexualism is someone who undergoes procedures to assume both the physical characteristics of the opposite sex and gender roles. Transsexualism often overlaps with transgenderism while transgenderism more commonly stand independently.

Now we ask the question: Is it fair for athletic organizations to require biologically female athletes to compete against trans women, or those whose X and Y chromosomal combination has played a factor in guiding their body’s development? Male sex organs and their accompanying hormones flood a male’s body from birth to the point of transition. This plays a factor in their physical development in tangible, observable ways.

Partly due to these factors, science contends that the average difference between the performance of male and female athletes of equal merit is approximately 10%. However, this figure can vary significantly. For example, Samuel Groth’s record 163.7 mile per hour (mph) tennis serve is 20% faster than Sabine Lisicki’s female record of 131 mph. In 2017, Blake Bolden set the National Women’s Hockey League (NWHL) record for hardest shot at 87 mph. For comparison’s sake, the slowest shot ever recorded in NHL Hardest Shot Competition was Al McInnins’ 93.0 mph slapshot in 1993, making a 6.5% difference between Bolden and McInnis. The two hardest NHL shots were recorded Zdeno Chara (108.8 mph) and Shea Weber (108.5 mph). Each were approximately 20% faster than Bolden’s record.

Despite this, we still require our women to compete against male-to-female transsexuals in physical, aggressive competitions. Should those who are post-op be able to compete against those who are pre-op? Should post or pre-op transsexual woman be able to compete against biologically born women without exception? How do we reconcile our desire to maintain fair competition in athletics with our desire to inclusivity?

Lets explore the case of the MMA fighter Fallon Fox, who was born male and between the ages of 30 and 31 underwent sex-reassignment surgery and began professionally fighting as a woman in 2012. First off, trans women are required to keep their testosterone levels beneath 10 nmol/L for at least 12 months prior to competing in an effort to negate some of the biological advantages associated with being born male. Neverthless, there are physiological differences that would result from living one’s life for the first 25-to-30 years in a male body with the aforementioned male-specific sex differences; for example, on average males have a higher bone density than females. For example, while female bones stop growing at the age of 18, male bones stop growing at age 21, providing men three additional years of bone growth. To make things more complicated, there is evidence to suggest that the hormone estrogen is related to higher bone density, thus making the likelihood that Fox, to a greater degree compared to that of the other women with which she competes, has high bone density that may give her an advantage in the amount of physical stress she could endure. However, while hormonal therapy assists bone density, it does not counteract bone growth.

Of course, each demographic has advantages and disadvantages between them, but the question should be: are there statistically relevant differences to warrant caution when encouraging or promoting trans competition against non-trans athletes in such physically demanding sports? Is it reasonable to consider having trans-exclusive sporting leagues such as TWMMA (Trans Women’s Mixed Martial Arts) or the TWNBA (Trans women’s National Basketball League)? For the interest of fairness, we may need to establish separate leagues for the transsexual demographic.

An article from ABC titled “Transgender teens outrun track competitors but critics close behind” published June 13, 2018, brings up the discussion of pre-hormone and operation trans women who compete as teenagers against biologically female classmates. One of the questions considered is whether two trans women have an unfair physical advantage over the biological women competing against them, to which Chris Moiser, a trans man, was quoted saying, “We can’t just assume that these athletes are winning because they’re transgender. It’s possible that they’d be beating these other student-athletes if they were cisgender.” Yet this does not make sense, for if these athletes were cisgender they would not have been competing against the same student-athletes. Both of these trans women athletes earned first and second place prizes in their respective track competitions.

At the other end of this discussion, though admittedly under less scrutiny, is the fairness of having female-to-male transexuals compete against biological men. This question has less relevance as it is an individual choosing to potentially put themselves at a greater physical risk. However, we must still dissect the first question. Transsexuals in sports may be the greatest gray area of modern society’s progressive stance. For the issue of male-to-female trans demographic, there are a multitude of factors that can come into play when discussing physical advantages, from that of testosterone development during the prenatal development up to whatever age an athlete starts their transition, to the innate advantages of bone density and its potential strengthening due to the transition hormone therapy.

Finally, we must explore the social ramifications. Considering the aforementioned 10% between male and female counterparts of equal talent, if we entertain the idea that hormonal therapy negates all androgen-afforded advantages, then this conversation is redundant. However, if we consider the possibility that some advantages, such as bone density and bone size, are retained post-op, then we must consider that sub-par athletes in the men division may be elite competitors in the female division. For example, someone who is 3% below the standard male athlete in athletic prowess would hold a 7% advantage against female competition. If the transitional process saps another 5%, that competitor would still hold a 2% advantage. Opponents fear that sub-par athletes in the male division will be allowed to compete against biologically disadvantaged competitors based on self-identity rather than fairness. Proponents claim that this problem does not exist due to decreasing testosterone, which advocates say negates any biological advantages.

Currently, there isn’t enough evidence to suggest either side is right or wrong. We can use existing science to offer educated guesses, but until we collect comprehensive data that measures pre-operation athletic prowess against post-transition abilities, we cannot say with concrete certainty that MTF transsexual athletes enjoy an advantage over biological female athletes. Both sides seem to have scientifically sound arguments, though based on the information currently available, it seems that above-average MTF transsexual athletes (relative to biological sex) are able to both compete and thrive against their elite biologically female counterparts.