Transgender Women in Volleyball – The Science

A hot topic in the media recently caught my eye; Transgender athletes in competitive sport. Although the discussion might get heated, it is something that ultimately affects the entire volleyball community.

Tiffany Abreu, a transgender woman playing in the Italian A2 League, has put volleyball at the forefront of this discussion. Find out more about Tiffany’s backstory and Vollywood’s take on the current debate HERE.

I want to take a look at this subject, and share some of the science behind ‘gender transitioning’, which is the foundation of decision-making about Transgender athletes in sport.

Initially, it is important to get a handle on the terms involved in the discussion. In the NCAA Inclusion of Transgender Student-Athletes statement, Transgender is described as “an individual whose gender identity (one’s internal psychological identification as a boy/male or girl/woman) does not match the person’s sex at birth”. In this definition, the challenge arises between an individual’s psychological and physical sense of self.

Doctors attempt to address this imbalance by controlling the levels of androgen hormones in the person’s body. For Female-to-Male transformation, androgen hormones such as testosterone are administered and in Male-to-Female transformations these hormones are regulated by administering antiandrogens alongside female sex hormones like estrogen and progesterone. Testosterone is the most well-known of these hormones, and plays a large role in the growth and development of male characteristics. this includes increased muscle mass and inhibition of fat storage, as well as the development of male sexual reproductive organs. In sport, contention usually centres around Male-to-Female transitions due to the effect these physical characteristics lead to on performance.

The presence of these hormones has been shown to have a profound effect on a person’s ability to develop strength and express high force. Studies comparing World Record performances in track and field have shown that male athletes outperform female athletes of the same discipline by 11-18% in athletic events. Due to these responses, the level of androgen hormones in the body are often a primary talking point in the discussions considering sports performance.

It’s important to bear in mind that these hormones are present in both males and females, and that their levels vary – even within gender. During childhood, androgen hormone levels are similar between boys and girls. This changes during puberty, causing the physical changes we associate with that developmental stage.

During the process of gender-transitioning, levels of androgen hormones are managed carefully. It has been shown that within 12-months of treatment, physical characteristics like muscle mass and fat storage of transitioned males and females reach levels associated with their selected gender. This has therefore been used as the benchmark for transitioned women to compete on a level footing in female sport, according to the IOC Stockholm Consensus.

But what about perceptual-cognitive skill development? The differences that naturally develop playing the male and female versions of our sport.

This is an interesting consideration which seems to be under-discussed, if at all. Variations in the speed of play present different challenges to the athletes, placing different cognitive requirements on the athlete and stimulating different cerebral adaptations to performance. These guide the interactions between the athlete’s brain, body and environment, which form the basis of his or her understanding of – and interaction with – the game.

Does this difference in the speed required to read the game impact on transitioning players? Is this something that can/should be regulated? Does this skew our understanding of what impacts on the performance level of athletes transitioning between genders?

The human body is an incredible and intricate system, delicately balancing a vast number of complex inputs to achieve any given output. Although science is on a steep developmental curve, our understanding of these complex systems is still growing. We may have the capacity to redress the hormonal imbalance for transgender individuals, helping them to gain balance between their psychological and physical position. But we do not yet have all the answers about the long-term effects this may have on the body, how this physical change interacts with previous motor control and psychological characteristics, or the impact this has on performance in competitive sport.

Ultimately, all men are not created equal, and all women are not created equal. It’s an inherent fact of all sports – including volleyball – that we are not on a level playing field…

Whichever side of the debate you find yourself on, be sure to arm yourself with facts.

Sources of Information

COMBEN, L. (1996). Transgender issues in sport. Problems, solutions and the future. Research paper, Master of Laws, University of Melbourne.

DEVRIES, MC. (2008). Do transitioned athletes compete at an advantage or disadvantage as compared with physically born men and women: A review of the scientific literature. Preparing for the Promising Practices: Working with Transitioning/Transitioned Athletes in Sport Project. http://www.caaws.ca/e/wp-content/uploads/2013/02/Devries_lit_review2.pdf

GOOREN, L.J.G. & BUNCK, M.C.M. (2004). Transexuals and competitive sports. European journal of endocrinology, 151, 425-429. http://www.eje-online.org/content/151/4/425.full.pdf

IOC STOCKHOLM CONSENSUS (2015) https://stillmed.olympic.org/Documents/Commissions_PDFfiles/Medical_commission/2015-11_ioc_consensus_meeting_on_sex_reassignment_and_hyperandrogenism-en.pdf

NCAA Inclusion of Transgender Student-athletes. (2011) https://www.ncaa.org/sites/default/files/Transgender_Handbook_2011_Final.pdf

VLAHOPOULOS, S. et al. (2005). Recruitment of androgen receptors via serum response factor facilities expression of a myogenic gene. The journal of biological chemistry. 280 (9), 7786-7792. http://www.jbc.org/content/280/9/7786.full.pdf