The participation of trans athletes in sport – a transformation in approach?

This article discusses the issues surrounding participation of trans athletes in sport, in particular in light of the IOC's new Transgender Guidelines

  1. Intro
  2. The key issues
  3. How do trans athletes fit in to the male/female athletics categories?
  4. The current regulatory responses and the new IOC Transgender Guidelines
  5. National law requirements
  6. Dutee Chand
  7. The U.K.
  8. The challenges
  9. Current approaches

Bruce (now Caitlyn) Jenner won a gold medal in the men's decathlon at the 1976 Olympic Games. However, she is perhaps now better known for her recent 'coming out' as transgender. 

In doing so, she highlighted an issue that the sports world is having to grapple with on an increasingly frequent basis, namely, how to deal with the participation of trans athletes in sport. 

This is very much a live issue, from grass roots right up to the elite level (for example, Chris Mosier recently became the first openly trans man to make a US men's national team, competing in the sprint duathlon at the Duathlon National Championships).1

This article considers the key issues that arise in relation to the participation of trans athletes, the different approaches taken by sports governing bodies (including the recently-revised IOC Transgender Guidelines), the interplay with national laws, and some of the legal challenges involved.

For the purposes of this article, the umbrella term 'trans' is used to refer to individuals whose own gender identity is different from the biological sex assigned to them at birth (whether or not they have undergone any form of medical intervention).

The key issues

The vast majority of sports divide competition into male and female categories.2

This is due to the significant physical advantages enjoyed (on average) by men from puberty onwards3,  which at elite level result in a gulf in sports performance between the sexes. For example, the world records in athletics show an average performance difference between men and women of around 12%.4

These physical differences between the sexes are thought to be due, principally, to the much higher levels of testosterone produced by males from puberty onwards, giving males greater strength and power than females5.  As a result, separation of the sexes is therefore required to allow for fair and meaningful competition, as well as to address potential health and safety concerns (for example, in contact sports).

This notion of fair and meaningful competition goes to the very essence of what sport is about. It reflects the underlying need to preserve the uncertainty of the sporting outcome, with success being determined by those particular factors that are valued by the sport in question (such as natural talent and training). 

And it is this need that underlies the various dividing lines that are drawn in sport, such as age and weight categories, and the numerous Paralympic classifications. It would not, for example, be fair or meaningful for a flyweight boxer to compete against a super heavyweight boxer: there is little doubt who would win, and it would not celebrate any worthwhile sporting values. 

Similarly, if women were required to compete against men, they would have very limited opportunities to succeed (at least at the elite level), and would not be rewarded for their sporting excellence or incentivised to make the sacrifices needed to reach their potential.

How do trans athletes fit in to the male/female athletics categories?

The division of competition into male and female categories raises a number of issues when it comes to the participation of trans athletes in sport:

  1. It is generally accepted that prior to puberty (when male and female testosterone levels are similar) there is little physical difference between the sexes, and mixed sex sport is often permitted (for example, the English FA allows mixed football up to the under 18 age group).  Accordingly, there appears to be (and should be) little issue regarding the participation of trans athletes, in line with their gender identity, at this stage.

    For example, many international and national bodies (including World Rugby, the International Tennis Federation, the English FA and the Rugby Football League) allow individuals who have undergone female-to-male sex reassignment before puberty to participate as males, and individuals who have undergone male-to-female sex reassignment before puberty to participate as females, without restriction6.

  2. After the onset of puberty, however (when male serum testosterone levels increase to around ≥10 nmol/L7, while female testosterone levels remain at around 0.1-3.08 nmol/L), the physical advantages enjoyed by men raise fairness and safety concerns in relation to the participation of trans athletes in line with their gender identity.

    In particular, a male-to-female transsexual might be thought to have an unfair performance advantage over other women (raising concerns as to fair competition and the safety of competitors), whereas a female-to-male transsexual might be thought to be at a disadvantage compared to other men (raising safety concerns in relation to their own participation). Sports governing bodies have to decide how best to address these difficult issues.

The current regulatory responses and the new IOC Transgender Guidelines.

The regulatory position regarding the participation of trans athletes in sport is complex. In particular, there is presently no consensus among sports regulators as to how best to respond to the sporting challenges, and no uniform approach. 

In some sports the issues are simply not acknowledged or addressed at all (as, for example, in international cycling). In others, the issues are addressed in a variety of different ways, from the very restrictive to the very permissive and inclusive8.  For example: 

  1. One very restrictive approach is CrossFit's 'female at birth' policy, which requires that all competitors in the female category have been 'born as a female'. This rather blunt and exclusionary approach is currently being challenged before the US courts9, and it is certainly a stark contrast to the more nuanced positions discussed below10. Indeed, the LPGA voted to remove a similar rule back in 2011 following a challenge by transgender golfer Lana Lawless11.

  2. Another relatively conservative approach was the 2003 IOC Stockholm Consensus (now replaced by the new IOC Transgender Guidelines), which set out recommendations applicable to the Olympic Games12. The IOC consensus provided that individuals undergoing sex reassignment after puberty would only be eligible to participate in the competition category of their affirmed sex if:
    1. surgical anatomical changes had been completed, including external genitalia changes and gonadectomy (removal of the ovaries or testes);  
    2. legal recognition of their affirmed sex had been conferred;
    3. hormone therapy had been administered for a sufficient length of time to minimise gender-related advantages in sport; and
    4. eligibility should begin no sooner than two years after gonadectomy.

  3. Many international and national federations presently apply the 2003 IOC Stockholm Consensus to their own competitions, sometimes with certain tweaks.13

    To take one example, under the IAAF's current regulations14 a male-to-female transsexual's eligibility to compete in female international athletics competition is dealt with by an expert medical panel on a case-by-case basis.

    The athlete will be eligible to compete in women’s competition provided that her medical treatment following sex reassignment has been administered for a sufficient length of time so as to minimise any advantage in women’s competition. To assess this, the panel looks at a range of factors: 
    1. the athlete's age; 
    2. whether sex reassignment took place pre or post-puberty; 
    3. the nature of the sex reassignment procedure undertaken; 
    4. the period of time since completion of the sex reassignment procedure; 
    5. the athlete's androgen levels; and 
    6. the nature, duration and results of any treatment and monitoring undertaken following completion of the sex reassignment procedure.

      Notably, however, there is no mandatory minimum waiting period following the reduction of the athlete's androgen levels. Meanwhile, female-to-male transsexuals are eligible to participate in men's competition if legal recognition of their male sex has been conferred.

  4. As scientific understanding developed, the 2003 IOC Stockholm Consensus was much criticised15  as imposing overly stringent and costly requirements on trans athletes, including requiring completion of surgical anatomical changes (and ignoring non-surgical alternatives, i.e. hormone therapy); the need for legal recognition of the person's affirmed sex, which in some jurisdictions is simply not possible under national law; and the mandatory two year waiting period following gonadectomy.

    As a result, the IOC recommendations (now the 'IOC Transgender Guidelines') have recently been radically revised and provide for a much more inclusive approach.16

    The new guidelines set out recommendations for international federations and others to consider when adopting their own rules in this area. In summary, those who transition from female to male are eligible to compete in the male category without restriction. Those who transition from male to female are now eligible to compete in the female category provided that:
    1. their declared gender identity is female (which declaration cannot be changed, for sporting purposes, for at least four years); and 
    2. their total serum testosterone level has been below 10 nmol/L for at least 12 months (although it is important to note that a longer time period may be imposed on a case-by-case basis, depending on whether 12 months is sufficient to minimise any advantage in women's competition in the circumstances of the particular case17), and it remains below 10 nmol/L throughout the period of desired participation.

      Compliance with those conditions may be monitored by testing, and in the event of non-compliance the athlete’s eligibility for female competition will be suspended for 12 months.

  5. Many national sports bodies take a yet more permissive approach, particularly for domestic competition. One interesting example from the UK is the English recently issued policy governing domestic football, which is again focused on testosterone levels.18

    In particular, for players aged 18 and over eligibility is determined on a case-by-case basis, having regard to the safety of the applicant and fellow players, and the need to ensure fair competition. For male-to-female transsexuals there is an initial presumption that those requirements are met where hormone therapy or gonadectomy results in testosterone levels in the female range for an appropriate length of time so as to minimise any potential advantage.

    Similarly, for female-to-male transsexuals there is an initial presumption that those requirements are met where hormone therapy results in testosterone levels in the male range for an appropriate length of time so as to minimise any potential advantage (presumably enjoyed by the applicant's male competitors, rather than by the applicant himself). However, there is also discretion to allow participation even in the absence of hormone therapy or gonadectomy. Like the IAAF, there is also no mandatory minimum waiting period.

    Also of interest are Badminton England19 and British Rowing20, which presently follow the 2003 IOC recommendations for international competition but take a less stringent approach at domestic level. In particular, in both of those sports a male-to-female transsexual who transitioned post-puberty is able to compete in domestic female competition on providing evidence that her testosterone levels have been brought within the female range (or alternatively, in the case of rowing, that she has had a gonadectomy).

    One key example from the US is the National Collegiate Athletic Association (NCAA) policy, which sets out recommendations for the participation of transgender students in NCAA sports21. Again, this takes a less stringent approach, for example, recommending that male-to-female transsexuals be eligible to participate in women's competition after completing one year of testosterone suppression treatment (similar to the new IOC criterion).

  6. Unsurprisingly, one of the most permissive and inclusive policies is that adopted for the Gay Games. This allows for participation based on (among other things) legal sex alone, or where the individual can demonstrate that they have been living in the particular gender for at least two years, or have been undergoing hormone treatment for at least one year22

National law requirements

Whatever approach is taken, sports must also ensure that they comply with applicable national law requirements. This is well illustrated by the recent interim award in Chand v AFI & IAAF23,  concerning the separate but related issue of the eligibility of female athletes with hyperandrogenism (elevated levels of natural testosterone) to compete in women's competition. 

Dutee Chand

In this case the question of whether the relevant sporting rules constituted unlawful discrimination (under, among other things, the laws of Monaco) was discussed at length, and the IAAF was required to demonstrate, on the balance of probabilities, that the restrictions placed on participation of such athletes in women's competition were necessary and proportionate to the achievement of a legitimate aim (namely, the preservation of fair competition). 

In that respect, although the court accepted that the 'IAAF has introduced the Hyperandrogenism Regulations to provide for fair competition and a level playing field within the female category … [and] the Hyperandrogenism Regulations are therefore intended to pursue a legitimate objective', it found that the IAAF had not established that hyperandrogenic athletes 'enjoy such a substantial performance advantage over non-hyperandrogenic female athletes that excluding them from competing in the female category, and thereby excluding them from competing at all unless they take medication or undergo treatment, is a necessary and proportionate means of preserving fairness in athletics competition and/or policing the binary male/female classification'. 

The court therefore suspended the application of the regulations pending the submission of further evidence on that issue by the IAAF24

The U.K.

Similarly, in the UK the Gender Recognition Act 2004 provides that the participation of trans athletes may only be prohibited or restricted in gender-affected sports (i.e. sports where the physical strength, stamina or physique of average persons of one gender would put them at a disadvantage to average persons of the other gender) where it is necessary to do so to ensure fair competition or the safety of competitors25.

The Sports Council Equality Group (comprising representatives of the sports councils of England, Northern Ireland, Scotland, Wales and UK Sport) has issued further detailed guidance on those requirements26,  suggesting different approaches for contact and non-contact sports, and at domestic and international level. 

While various policy options are suggested, they are all heavily focused on testosterone levels (for example, recommending that a male-to-female transsexual be eligible to compete in women's competition if she can show that hormone therapy has brought her testosterone levels within the female range or that she has had a gonadectomy; and, for contact sports, a recommendation that a female-to-male transsexual have testosterone levels in the male range in order to be eligible to compete in men's competition).27

The challenges

As is clear from the above, the participation of trans athletes in sport is without doubt a complex area, with no obvious or straightforward solution. However, it is not something that sport can ignore, and there are many benefits to having a clear and considered policy that seeks to preserve competitive balance and address any safety concerns, while also providing trans athletes with an opportunity to participate.

As to what such a policy might look like, that may well depend on the sport in question and on the particular fairness and safety considerations that apply (for example, in contact sports versus non-contact sports).28

As seen in the existing policies, the approach may also differ as between elite-level competition and grass roots/recreational sport (see, for example, the very inclusive policy adopted for the Gay Games, which may well not be appropriate at elite level).

That said, there is certainly scope for sport to take a more proactive and joined-up approach in this area, for example, by looking at developing certain broad principles that can be universally applied, as well as ensuring that policies are evidence-based and in line with current scientific and medical understanding29.  The new IOC Transgender Guidelines will also serve as a useful starting point for discussion.

Current approaches

As to the current approaches taken by sports bodies, the recent trend is most definitely towards a more nuanced and permissive approach. In particular, the new IOC guidelines are, in the author’s opinion, to be welcomed and represent an important step forward in this area. 

It is also worth observing that a key factor appearing in almost every approach is the consideration of testosterone levels (although this does present its own challenges in relation to the need for ongoing monitoring for compliance). 

On the other hand, an approach based exclusively on testosterone levels (such as that of the English FA, and suggested by the Sports Council Equality Group) may not always cater for all scenarios (for example, factors such as height and size may also be relevant in certain sports). The requirement that female-to-male transsexuals have testosterone levels 'in the male range' (ostensibly due to safety concerns) also seems potentially problematic (in particular, the 'male range' is not specified in such policies, and while a normal male range does exist there will be males with testosterone levels outside of that range).

In contrast, the IAAF approach, while involving a large discretionary element, does have the benefit of allowing for a case-by-case assessment in light of certain broader principles.     

Looking to the future, to add to the already complex position, a further challenge for sports regulators is the increasing ease of changing one’s legal sex in some jurisdictions30, compared to the difficulty or even impossibility of doing so in others. As a result, sports authorities will need to consider whether legal recognition of trans athletes in their preferred sex remains a necessary requirement (for example, where an individual has undergone full sex reassignment but remains unable to change his/her legal sex), or indeed a sufficient requirement (for example, where an individual has been able to change his/her legal sex without undergoing any form of medical intervention).31

In addition, while not explored further in this article, it is also worth noting two separate but related issues (each complex in their own right, and outside the scope of the IOC Transgender Guidelines):

  1. how to deal with the increasing recognition of a 'third sex'32 i.e. something other than 'male' or 'female', and sometimes referred to as 'X' (now recognised in various countries including Australia, Bangladesh, Germany, India, Nepal, New Zealand and Pakistan); and 
  2. how to address the participation of intersex athletes i.e. individuals with so-called 'differences of sex development', who have a mixture of male and female sexual characteristics and may consider themselves either male or female.33

This piece was originally written for and first published by LawInSport.  A copy of the article is available to view on LawInSport here.

  1. See Chris Mosier’s athlete profile at!about-chris/c1ic2.
  2. Among the handful of exceptions to this are the various equestrian disciplines and certain sailing events, where (presumably) it is thought that men and women can compete fairly and safely against each other.
  3. See, for example, the Sports Council Equality Group guidance, Transsexual People – Eligibility to Compete in Domestic Competition,, pages 9-11, discussing the sex-related differences that contribute to sports governing bodies organising separate male and female competitions (including height, strength, power, muscle mass and aerobic capacity), and looking at specific examples in badminton and hockey.
  4. See the IAAF World Records, available at (last viewed 31 Jan 2016).
  5. See e.g. Gooren LJ, The significance of testosterone for fair participation of the female sex in competitive sports, Asian Journal of Andrology (2011) 13, 653-654; Handelsman and Gooren, Hormones and sport, Asian Journal of Andrology (2008) 10, 348-350; Tucker, R. & Collins, M., The science of sex verification and athletic performance, Int J Sports Physiol Perform, 2010; 5: 127–139, pp. 131 and 134.
  6. See, respectively,, (pages 25 and 44-45) and
  7. See e.g. Turpeinen et al (2008), Determination of testosterone in serum by liquid chromatography-tandem mass spectrometry, Scandinavian Journal of Clinical and Laboratory Investigation, 68:50–57.
  8. Although not completely up-to-date, has compiled a large number of policies governing the participation of trans athletes in sport.
  9. Chloie Jonsson v CrossFit Inc, Superior Court of California.
  10. Madison Park, ‘Transgender athlete sues CrossFit for banning her from competing as female’,, 7 March 2014, last viewed 31 Jan 2016,
  11. Katie Thomas, Transgender Woman Settles Suit Against Two Organizations, NY Times, 3 May 2011, last viewed 31 Jan 2016,
  12. Statement of the Stockholm consensus on sex reassignment in sports,
  13. This includes (among others) the International Hockey Federation (FIH), the International Ski Federation (FIS), the International Rowing Federation (FISA), the International Cricket Council (ICC), the International Shooting Sport Federation (ISSF), the International Tennis Federation (ITF), the Rugby Football Union (RFU), the International Cycling Union (UCI) and World Rugby.
  14. IAAF Regulations Governing Eligibility of Athletes Who Have Undergone Sex Reassignment to Compete in Women's Competitions, available at (last viewed 31 Jan 2016).
  15. See e.g.
  16. IOC Consensus Meeting on Sex Reassignment and Hyperandrogenism November 2015, ‘IOC Transgender Guidelines’, available to view at (last viewed 31 Jan 2016).
  17. The standard 12 month 'waiting period' is based on the findings of a study demonstrating that the effects of cross-sex hormones used during sex reassignment reach their maximum effects after one year of administration, i.e. no further changes were observed after that point: Gooren LJ, Bunck MC, Transsexuals and competitive sports, Eur J Endocrinol (2004) 151, 425-429. See also Gooren LJ, The significance of testosterone for fair participation of the female sex in competitive sports, Asian Journal of Andrology (2011) 13, 653-654.
  18. Rules and governance, ‘LGBT Football’, available to view at (last viewed 31 Jan 2016). The Rugby Football League also takes a similar approach.
  19. Badminton England rules and regulations, available to download at (last viewed 31 Jan 2016).
  20. British Rowing, Policies and Guidance, Transgender and Transexual policy, available to download at (last viewed 31 Jan 2016).
  21. NCAA Transgender Handbook, available to download at (last viewed 31 Jan 2016).
  22. Gay Games Gender in Sports Policy, available to view at (last viewed 31 Jan 2016).
  23. Ms Dutee Chand v Athletics Federation of India and The International Association of Athletics Federations, CAS 2014/A/3759,
  24. See footnote 23, above, especially at paras 508, 532 and 547-548.
  25. This position is also reflected in the Sex Discrimination Act 1975 and the Equality Act 2010.
  26. Available at For further information on these requirements and related matters (including appropriate access to sports facilities and drug testing), see the Department for Culture, Media and Sport guidance at
  27. For a discussion of the position in the US, see Brown, The Transgender Student-Athlete: Is There a Fourteenth Amendment Right to Participate on the Gender-Specific Team of Your Choice?, 25 Marq. Sports L. Rev. 311 (2014).
  28. The DCMS guidance at para 26 notes that 'Individual sports are best placed to decide on what basis a situation might arise whereby a transsexual person's participation poses risks to safety or fair competition' (
  29. See Gooren LJ, Bunck MC, Transsexuals and competitive sports, Eur J Endocrinol (2004) 151, 425-429 and, for a more recent example looking at distance running, Harper, Race Times for Transgender Athletes, Journal of Sporting Cultures and Identities, Volume 6, Issue 1, pp.1-9.
  30. For example, in Argentina, Columbia, Denmark, Malta and the Republic of Ireland, it is now possible to change one's legal sex by self-declaration alone, without the need for medical treatment or diagnosis.
  31. See, for example, the new IOC Transgender Guidelines, which require a male-to-female transsexual to declare that their gender identity is female (which declaration cannot be changed, for sporting purposes, for a minimum of four years), but do not require legal recognition of the person's female sex.
  32. See e.g. ‘Gender neutral passports move a step closer to reality after Labour backing’, 20 March 2015,
  33. For further discussion on this topic, see the recent CAS decision in Chand v AFI & IAAF (footnote 23, above).

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