In Olympic competition, the men’s shot is 7.26kg whilst the women’s is 4kg. The men still ‘put’ it further. This is because of the typical strength and power differences between the two sexes. (Book cover image from my personal copy of Komi, P.V. (ed.) (1992), Strength and Power in Sport, Hodder & Stoughton).

Male Sports Performance Advantage

Dr Tony Lycholat

Science-based Questions

What questions would you ask a male-to-female transgender athlete? Someone like the New Zealand weightlifter, Lauren Hubbard, for example?”

It was a simple enough request, posed by a friend who happens to be an experienced sports journalist.

I’d acknowledge that Hubbard is following the current rules for competition developed by the sport’s national and international governing bodies (following International Olympic Committee guidelines), then be factual and scientific, was my reply. As much as possible, I’d want to establish a platform for my questions with a little sports science.

For example, I might say: according to Professor Ross Tucker, a sports scientist who was part of Caster Semenya’s team in her Court of Arbitration for Sport case (1), “…the presence of the Y chromosome is the single greatest performance advantage a person can have. That doesn’t mean that all men out-perform all women, but it means that the Y chromosome and specifically the SRY gene on it, which directs the formation of testes and the production of testosterone, is a key criterion on which to separate people into categories” (2).

This would allow me to clarify for a general audience that rare differences of sexual development (Semenya is a DSD athlete) have nothing to do with being transgender (3). I’d then ask Hubbard:

“Do you have the Y chromosome? And if you do, surely this means you have an unfair athletic performance advantage?”

I’d probably continue with: Professor David Handelsman, an endocrinologist, has made the biological observation that, “elite athletic competitions have separate male and female events due to men’s physical advantages in strength, speed, and endurance so that a protected female category with objective entry criteria is required. Prior to puberty, there is no sex difference in circulating testosterone concentrations or athletic performance, but from puberty onward a clear sex difference in athletic performance emerges as circulating testosterone concentrations rise in men because testes produce 30 times more testosterone than before puberty with circulating testosterone exceeding 15-fold that of women at any age” (4).

The obvious follow-on questions become:

“Have you experienced male puberty? If you have, surely this means you have another unfair performance advantage?”

Next, I would consider a little physiology. Muscle physiologists have shown that with previous training, muscles develop an increased number of specialist cells called myonuclei. This is especially true in the presence of testosterone following male puberty. When training stops, these myonuclei become dormant, becoming active again when training re- commences (5).

The questions based upon this would then be:

“Were you someone who trained for sport previously? Could your previous athletic training as a man prior to transitioning, along with retained, cellular muscle memory (myonuclei), give you yet another unfair advantage?”

Sadly, such questions are unlikely ever to be asked. It would seem that many journalists fear being called ‘transphobic’ — and, understandably, would rather not endure the usual activist ‘pile-ons’ and emails to their employer demanding they should be sacked — simply for applying a little science. Of course, being pro-biology in sport is clearly not the same as being ‘anti-trans’. Like many people, I’m still waiting for the essential research and much needed rational debate on the important topics of fairness, safety and inclusion in sport that, thanks to aggressive trans-activists, never seems to materialise (6).

Theory into Practice

Put most simply, when it comes to sport:

Male performance advantage = presence of the Y chromosome + responsiveness to testosterone + male puberty + previous training (including cellular ‘muscle memory’)

What does this mean, practically? I’m increasingly of the opinion that those who argue for self-identifying, male-to-female transgender participation in the female sex category have never competed in sport. They certainly can never have coached or set foot on an athletics track. Let me explain.

Over and above the entirely obvious differences in athletic performance between the two sexes observed at every single training session in post-pubertal athletes, if you coach athletics, or study it scientifically, you’ll find yourself poring over comparative data. In terms of biomechanics, where once the serious student of athletics was limited to one or two now classic texts such as Geoff Dyson’s The Mechanics of Athletics (7) or, if you could find a copy, Schmolinsky’s Athletics Training: Track and Field in the GDR (8), there are now ongoing research projects all around the world that throw up information on elite athletes constantly. One fascinating resource is World Athletics itself, since this organisation publishes anthropometric as well as biomechanical data captured during major championships.

For example, looking at the reports from the 2017 World Championships for just one event, the shot put (9), the female competitors were between 1.72 and 1.85m in height, and between 71 and 115kg in bodyweight.

At the same championships in the same event, the male competitors were between 1.81 and 2.01m in height, and between 115 and 136kg.

Yet of far more interest to the scientist are the biomechanical factors that influence the final distance achieved in the shot: for example, things like release velocity, release angle and height of release. The shot is a heavy implement and simple laws of physics apply. The height of release is clearly related to the height of the athlete, whilst release angle achieved, so important when aiming for distance, is related to technical training. Of greatest importance perhaps is the ‘resultant velocity of the shot at release’: its release velocity. Unsurprisingly, the best throwers typically achieve the greatest release velocities (9).

The release velocity difference between the sexes is, in performance terms, quite astounding: for the elite women the release velocity at these World Championships was 12.31–13.31 metres/sec. For the men, it was 13.24 –14.15 metres/sec.

In these championships in the women’s competition, the top three distances were: Gong, 19.94m (gold); Marton, 19.49m (silver); Carter, 19.14m (bronze). In the men’s competition the results were: Walsh, 22.03m (gold); Kovacs, 21.66m (silver); Zunic, 21.46m (bronze). Of the men, the gold medallist, Walsh, achieved the greatest release velocity. Of the women, the gold medallist, Gong, was close to achieving the greatest release velocity (with 13.24 metres/sec). Her winning distance was aided by an optimum release angle and height of release.

Maximum strength

Maximum strength (the ability to exert maximum force) is crucial in the shot since the release velocity depends on the applied force (and the distance through which it is applied). Starting from ‘zero velocity’, the athlete needs to generate and apply force so that the shot accelerates rapidly to leave their fingers at maximum height, optimum angle and with the greatest possible release velocity; all from within a circle of just 2.135m (7 feet) in diameter.

Why is the final release velocity of the shot between the sexes so different in elite competition?

Fundamental principles of sports science, and coaching experience, tell me that this is because of the typical differences in maximum strength between men and women. Maximum strength is especially important at the very start of the shot put (since there is the athlete’s mass to be overcome), whether the athlete is using a rotational or glide technique. In the absence of maximum strength data for each shot putter at these championships (the available biomechanical reports do not include this), related information from elite weightlifting is helpful.

The ‘first pull’ in Olympic weightlifting depends on maximum strength. In the 2019 International Weightlifting Federation (IWF) World Championships for the weight classes that allow direct comparison, the snatch lift in the female competition (55kg and 81kg weight classes) was won with lifts of 99kg and 111kg respectively. In the men’s competition, the snatch was won in the same weight classes with lifts of 128kg and 171kg (10).

In the few biomechanical studies that have investigated the differences between men and women and the execution of the snatch lift*, it would appear that it is what happens in the first pull, when that incredibly heavy bar needs to begin its rapid acceleration from zero velocity, that differs between the sexes (11, 12).

Sex matters in athletics

What if there was a woman of similar size, technique and training history to a man in the shot? The great Dame Valerie Adams — twice Olympic champion and four times World outdoor champion — fits the bill nicely (13). At 1.93m tall and 120kg (in competition), Adams is much like a male shot-putter in terms of height and weight. Her outdoor personal best is 21.24m, and this is approaching the kind of distance an elite male competitor achieves (see above). However, women use a 4kg shot whilst the men’s is 7.26kg.

In other words, even when you ‘match’ a big, athletic woman with years of serious training and competition under her belt with a big, athletic man who has also engaged similarly with training and competition, the man easily outperforms the woman.

I acknowledge that, in part, this could perhaps be explained by differences in body composition (typically, for the same bodyweight, men have a greater percentage of muscle mass), but I can think of other sex-based, physiological and biomechanical factors that will influence the expression of maximum strength and the development of power.

The bottom line is this: maximum strength is important when it comes to the throws in athletics, and in weightlifting — and indeed in every explosive, athletic event I can think of — and males have an advantage. Sex matters.

Have another look at the IWF results presented earlier: in the snatch, the man in the 55kg weight class lifted not just more (with 128kg) than the woman in the 55kg class (99kg) but also more than the woman in the 81kg class (111kg). In the real world of elite competition, it couldn’t be clearer. In addition, academic research that has looked at the relationship between maximum strength and weightlifting performance in 65 national and international weightlifters is confirmatory, even when every attempt is made to account for differences using various ‘scaling’ techniques, with researchers concluding that, “men are stronger than women, even when body mass and height are obviated by scaling methods” (14).

If you have no interest in athletics and reading this, you are realising for the first time that in the Olympics, in comparison with women, men throw things that are much heavier (and sprint over hurdles that are significantly higher), ask yourself: why might that be? Even the Olympic weightlifting bar that a man uses in competition has a different (grip) diameter to that used by a woman. There’s a reason: sex matters.

The mixed 4 x 400m Relay

This is where I really struggle with the International Olympic Committee’s transgender participation guidelines (15) and regard these, along with the unscientific anecdotes of IOC transgender adviser, Joanna Harper (16) with continued amazement.

Since ‘track and field’ really is just running, jumping and throwing, and performances are easily compared, the most obvious and practical examples of male performance advantage exist in athletics. Of course, elite athletic competitions have separate men’s and women’s events, so the casual viewer perhaps doesn’t necessarily appreciate sex-based performance differences immediately. Even big city marathons split the elite men’s and elite women’s fields.

However, since the recent introduction of the mixed 4 x 400m relay (two men and two women in each team, each completing a 400m leg in any order) the difference between men’s and women’s performances must be startlingly obvious even to the armchair observer. Have another look at the ease with which the male athlete (Michael Cherry) from the USA overtakes the female athlete (Justyna Swiety-Ersetic) from Poland during the World Athletics Championship final in Doha, 2019 (17). Now, recall that the social psychologist, Beth Jones argued for the inclusion of male-to-female athletes in women’s events saying that with such transgender participation, “women would try harder” (18). Not only did the incredibly naïve Jones insult all female athletes, she also made it clear she had little understanding of sport, or sports science.

The experienced and talented Swiety-Ersetic (Poland’s national record holder, with a 400m personal best of 50.41 seconds) was in the final of a World Championship and unlikely as a consequence to be taking it easy. Down the back straight, she was probably travelling at more than 8 metres per second. Unfortunately for her, Cherry (with a 400m personal best of 44.66 seconds), and just like every elite male 400m sprinter, was covering more than 9 metres per second.

The typical, often reported ‘10–12%’ differences in performance between men and women in athletic events (19) perhaps sound, to the non-sporty or the uninformed, like they might possibly be dealt with by ‘trying harder’ in training or competition. Seriously? Not a chance. In the 400m, an elite male sprinter has finished the race when the elite female still has 40m or more to go. Measure this out next time you go for a walk and think about it. You might consider taking something heavy with you to see how far you can throw it. Then imagine the extra strength and power needed to be able to throw something almost twice as heavy the same distance or more.

That’s the simple, observable reality of male sports performance advantage. The biological, physiological and biomechanical evidence for the sports performance differences between the sexes is clear and supported by all kinds of factual data. What isn’t known is how much of this performance advantage is lost ‘in transition’ across a variety of sports and events.

Out to Lunch

This is precisely where the IOC needed to start in 2015; and not with its slap-dash, back-of-an-envelope, unreferenced guidelines that give the impression of having been written in half-an-hour after a boozy, old boys’ club lunch in Lausanne. As an organisation that says it is committed to a ‘guarantee of fair play’ (15), the IOC seriously needs to deliver a scientific, evidence-based argument to support the contention that the individual who starts out with male sports performance advantage somehow loses all of this following just 12 months of hormone therapy.

The studies I especially want to see are not just those like the recent work of Lundberg et al (20) — as insightful as this is — which shows almost no loss in muscle strength after 12 months of transitioning in a non-athletic population. To accompany similar such investigations (which may refute or confirm these initial findings) I want to read good quality research regarding transitioning athletes, who are following the IOC guidelines, and who are still training seriously for competition.

Knowing what happens in elite sport regarding doping, I’d argue additionally that all athletes in such studies need to be tested for performance enhancing drugs of all descriptions randomly and regularly. If I can think of what an athlete might use to offset any potential negative effects (in terms of sports performance) of hormone treatment, so can someone else. And, if you don’t think any athlete would consider cheating, you really don’t know elite sport (21).

If you’ve managed to read this far and followed the links to the research references, you might well be thinking, “just how did intelligent, academically and clinically qualified members of the IOC’s medical and scientific committee manage to create such unscientific guidelines?” Indeed. It is perhaps no surprise that a number of women’s sports groups are currently lobbying the IOC, demanding a suspension of its current policy (22).


[*It may well be coincidental that Hubbard’s best lift is the snatch. In the 2019 IWF championships, Hubbard achieved 131kg (4th place) in the snatch in the +87kg weight class, the heaviest class for women. Hubbard’s bodyweight was given as 138.15kg. A lifter in the men’s +109kg class (the heaviest for men) of comparable weight is Ziaziulin, of Belarus, at 134.55kg. Ziaziulin also came fourth, with a snatch lift of 198kg.]


1. Appreciating the Caster Semenya case requires considerable reading and research. The references at the end of this piece are helpful:



4. Handelsman et al (2018) Circulating testosterone as the hormonal basis of sex differences in athletic performance.

5. Gundersen, K. (2016) Muscle memory and a new cellular model for muscle hypertrophy and atrophy.


7. Dyson, G. (1962) The mechanics of athletics. Hodder and Stoughton,

8. Schmolinsky, G. (1978) Track and Field: athletics training in the GDR. Sportverlag, Berlin.



11. Sezgin Korkmaz & Erbil Harbili (2015): Biomechanical analysis of the snatch technique in junior elite female weightlifters, Journal of Sports Sciences, DOI: 10.1080/02640414.2015.1088661

12. Harbili and Alptekin (2014) Comparative kinematic analysis of the snatch lifts in elite male adolescent lifters. Journal of Sports Science and Medicine, 13, 417–422.








20. Wiik, Anna & Lundberg, Tommy & Rullman, Eric & Andersson, Daniel & Mats, Holmberg & Mandić, Mirko & Brismar, Torkel & Olof, Dahlqvist & Setareh, Chanpen & N, Flanagan & Arver, Stefan & Gustafsson, Thomas. (2019). Muscle Strength, Size, and Composition Following 12 Months of Gender-affirming Treatment in Transgender Individuals. The Journal of clinical endocrinology and metabolism. 105. 10.1210/clinem/dgz247.

21. Ulrich, R. et al (2017) Doping in two elite athletics competitions assessed by randomised-response surveys. Sports Med; DOI 10.1007/s40279–017–0765–4


I have degrees in sports science, sports medicine, and elite coach development. I’ve written about exercise, sport, coaching, and mental health since 1982.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store