'That's ideology, not science' - Renowned sports scientist steps in on transwomen in rugby debate
Sports scientist Ross Tucker has waded into the debate over the participation of transwomen in rugby and the safety concerns around their participation in women’s rugby.
In July The Guardian revealed that World Rugby appear set to exclude transwomen from playing womens’ rugby on safety grounds following a workshop on the issue. A 38-page draft document suggested “at least a 20-30% greater risk” for a women who is tackled by a player who has gone ‘through male puberty’.
The news was greeted with heavy criticism from LGBTQ advocates, many of whom contend that the jury is still out on the scientific argument for excluding transwomen. This week Michelle Daltry, who represents LGBT+ Sport Cymru said: “We are asking rugby clubs at all levels of the game to stand with us against a ruling that is exclusionary and that will impact some of the most vulnerable people in the community”.
Now renowned sports scientist Ross Tucker has attempted to answer the question in an extensive Twitter thread on the thorny subject. Tucker, a World Rugby consultant, argues that transwomen athletes in rugby enjoy a significant advantage over their biologically female peers and that these advantages give rise to a higher risk of injury.
“This has been a common argument in the trans women in rugby debate. People have the idea that unless you *directly* study rugby AND show that TW cause injuries, it can’t be evidence based. Of course it can – there are peer reviewed studies that show two related things”
This has been a common argument in the trans women in rugby debate. People have the idea that unless you *directly* study rugby AND show that TW cause injuries, it can’t be evidence based. Of course it can – there are peer reviewed studies that show two related things (thread) https://t.co/oOwx725WIo
— Ross Tucker (@Scienceofsport) August 24, 2020
“First, you have so many studies that identify both performance determinants and risk factors for injury in rugby. Dozens of studies identify when injury occurs, and thus what the significant risks for injury are. Similarly, performance is multifactorial but is KNOWN to be significantly influenced by a handful of testable/measurable factors. In fact, these measurable factors are so crucial and “robust” that teams actually have minimum standards for them, and select or drop players based on achieving these targets. They’re not “guesses”.
2/ First, you have so many studies that identify both performance determinants and risk factors for injury in rugby. Dozens of studies identify when injury occurs, and thus what the significant risks for injury are. Similarly, performance is multifactorial but is KNOWN to be…
— Ross Tucker (@Scienceofsport) August 24, 2020
3/ …significantly influenced by a handful of testable/measurable factors. In fact, these measurable factors are so crucial and “robust" that teams actually have minimum standards for them, and select or drop players based on achieving these targets. They’re not “guesses”.
— Ross Tucker (@Scienceofsport) August 24, 2020
“Then second, you have a number of peer reviewed studies that have examined and described both the performance AND biological differences between M and F. So performance differences in tasks ranging from running to jumping to kicking to punching to throwing are known, and so too are biological factors underpinning the differences. For instance, it is known that throwing, kicking, punching, jumping, hitting etc are 20% to 160% better in males, elite & untrained, as a result of biological variables that include muscle mass, levers, tendons etc
4/ …Then second, you have a number of peer reviewed studies that have examined and described both the performance AND biological differences between M and F. So performance differences in tasks ranging from running to jumping to kicking to punching to throwing are known, and…
— Ross Tucker (@Scienceofsport) August 24, 2020
5/ …so too are biological factors underpinning the differences. For instance, it is known that throwing, kicking, punching, jumping, hitting etc are 20% to 160% better in males, elite & untrained, as a result of biological variables that include muscle mass, levers, tendons etc
— Ross Tucker (@Scienceofsport) August 24, 2020
“This is really important because if you know the outcome (B, performance), and you know the factors that contribute significantly to the outcome (A, biological variables), then it’s hardly a leap to surmise what would happen to B if A changes, or doesn’t change. Make sense?
6/ This is really important because if you know the outcome (B, performance), and you know the factors that contribute significantly to the outcome (A, biological variables), then it’s hardly a leap to surmise what would happen to B if A changes, or doesn’t change. Make sense?
— Ross Tucker (@Scienceofsport) August 24, 2020
“So you take these parallel streams, and next, consider 11 longitudinal studies, all peer reviewed, that show that T suppression only removes a very small part (or none) of the muscle mass, volume, or strength advantages, and doesn’t change skeletons. What does this mean?
7/ So you take these parallel streams, and next, consider 11 longitudinal studies, all peer reviewed, that show that T suppression only removes a very small part (or none) of the muscle mass, volume, or strength advantages, and doesn’t change skeletons. What does this mean?
— Ross Tucker (@Scienceofsport) August 24, 2020
“Remember that if B (performance or injury risk) is the result of A (biology), and you know that A is barely changed, then on what basis would you speculate that B is going to change meaningfully? You’d have to introduce something new to even make a start on this theory.
8/ Remember that if B (performance or injury risk) is the result of A (biology), and you know that A is barely changed, then on what basis would you speculate that B is going to change meaningfully? You’d have to introduce something new to even make a start on this theory.
— Ross Tucker (@Scienceofsport) August 24, 2020
“Basically, you’re surmising that no advantage DESPITE the persistence of measured biological advantages? That’s ideology, not science. We can get a whole lot more specific than this. Here’s one example, for injury risk factors…
“It is known that in rugby, injury is the result of excessive energy transfer to a player (this is literally the definition). This is a function of mass, speed and force exerted, along with the ability of a player to absorb that force/torque. So we have A, B and C = injury
9/ Basically, you’re surmising that no advantage DESPITE the persistence of measured biological advantages? That’s ideology, not science. We can get a whole lot more specific than this. Here’s one example, for injury risk factors…
— Ross Tucker (@Scienceofsport) August 24, 2020
10/ It is known that in rugby, injury is the result of excessive energy transfer to a player (this is literally the definition). This is a function of mass, speed and force exerted, along with the ability of a player to absorb that force/torque. So we have A, B and C = injury
— Ross Tucker (@Scienceofsport) August 24, 2020
“We know, for instance, that head injuries occur when head kinematics (acceleration) and kinetics (neck force and moments) exceed a threshold. So there are DIRECT links between these risk factors and the ‘inputs’, which are speed, mass and force applied in contacts.
11/ We know, for instance, that head injuries occur when head kinematics (acceleration) and kinetics (neck force and moments) exceed a threshold. So there are DIRECT links between these risk factors and the ‘inputs’, which are speed, mass and force applied in contacts.
— Ross Tucker (@Scienceofsport) August 24, 2020
“Now, we can take mass, just to *ILLUSTRATE* a point, and ask “What would happen in a typical male-bodied mass tackled a typical female bodied mass?”. In the elite game, we know the mass disparity, so we can model “typical vs typical” and we discover that the RISK FACTORS are 20% to 30% higher based ON MASS ALONE. Remember that injury is three variables – mass, strength & speed (or rate of force application, perhaps more accurate). So if we factor in strength disparities, plus speed, might the risk go up even more? Yes. Each may be additive.
12/ Now, we can take mass, just to *ILLUSTRATE* a point, and ask "What would happen in a typical male-bodied mass tackled a typical female bodied mass?”. In the elite game, we know the mass disparity, so we can model “typical vs typical” and we discover that the RISK FACTORS are
— Ross Tucker (@Scienceofsport) August 24, 2020
…20% to 30% higher based ON MASS ALONE. Remember that injury is three variables – mass, strength & speed (or rate of force application, perhaps more accurate). So if we factor in strength disparities, plus speed, might the risk go up even more? Yes. Each may be additive.
— Ross Tucker (@Scienceofsport) August 24, 2020
The premise of the model is evidence-based: Injury & performance are the DIRECT result of variables A, B & C. Thus, if you take A, B & C, and find:
a) They’re significantly higher in M than F;
b) Reducing T does not reduce A, B and C to female levels;
what can you conclude?
14/ The premise of the model is evidence-based: Injury & performance are the DIRECT result of variables A, B & C. Thus, if you take A, B & C, and find:
a) They’re significantly higher in M than F;
b) Reducing T does not reduce A, B and C to female levels;
what can you conclude?— Ross Tucker (@Scienceofsport) August 24, 2020
“The ONLY conclusion you can draw is that injury risk & performance will remain significantly elevated. To argue anything other than this means you have to redefine injury and negate variables that are KNOWN to significantly elevate performance. It’s impossible. On what basis will the contributing factors remain similar and the outcome change? The entire context will have to change. Please note – this does NOT mean that A, B and C are exhaustive.
“Things like technique and context modify risk, we know this. But you don’t need to assess this to make an evidence-based conclusion that risk will increase and fairness will be compromised when the links between the input and output are so clear. Also, it is acknowledged that more research is required – it would be great to actually quantify force in the tackles when mass, strength and speed are all factored in. We are committed to this research, but it’s not easy to do. You’re asking to quantify the biomechanics of this kind of situation across hundreds of simulations with different inputs. It’s not a fun watch:
15/ The ONLY conclusion you can draw is that injury risk & performance will remain significantly elevated. To argue anything other than this means you have to redefine injury and negate variables that are KNOWN to significantly elevate performance. It’s impossible. On what basis
— Ross Tucker (@Scienceofsport) August 24, 2020
16/ …will the contributing factors remain similar and the outcome change? The entire context will have to change. Please note – this does NOT mean that A, B and C are exhaustive. Things like technique and context modify risk, we know this. But you don’t need to assess this to…
— Ross Tucker (@Scienceofsport) August 24, 2020
17/… make an evidence-based conclusion that risk will increase and fairness will be compromised when the links between the input and output are so clear. Also, it is acknowledged that more research is required – it would be great to actually quantify force in the tackles when…
— Ross Tucker (@Scienceofsport) August 24, 2020
…mass, strength and speed are all factored in. We are committed to this research, but it’s not easy to do. You’re asking to quantify the biomechanics of this kind of situation across hundreds of simulations with different inputs. It’s not a fun watch: https://t.co/zfsAETDovm
— Ross Tucker (@Scienceofsport) August 24, 2020
“This kind of biomechanical study must be done, but it’s not quite as simple as this crude illustration suggests. But it WILL BE explored. But its absence is not sufficient to conclude that there’s no issue.
This has been a common argument in the trans women in rugby debate. People have the idea that unless you *directly* study rugby AND show that TW cause injuries, it can’t be evidence based. Of course it can – there are peer reviewed studies that show two related things (thread) https://t.co/oOwx725WIo
— Ross Tucker (@Scienceofsport) August 24, 2020
“There’s plenty of reason to link our knowledge of biology, performance and injury risk, and to ask how they outcomes change (they don’t) if the inputs change (they don’t, either. Which is kind of the point). So that’s the evidence-base. Incomplete? Yes. Guess? No way
20/ There’s plenty of reason to link our knowledge of biology, performance and injury risk, and to ask how they outcomes change (they don’t) if the inputs change (they don’t, either. Which is kind of the point). So that’s the evidence-base. Incomplete? Yes. Guess? No way
— Ross Tucker (@Scienceofsport) August 24, 2020
“Anyway, that’s all for now. The other common response is that some women are heavier/stronger/faster than some men, and since the ranges overlap, there should be no problem with cross-over, or case by case assessment. That’s all kinds of wrong, but it’s for another day. END
21/ Anyway, that’s all for now. The other common response is that some women are heavier/stronger/faster than some men, and since the ranges overlap, there should be no problem with cross-over, or case by case assessment. That’s all kinds of wrong, but it’s for another day. END
— Ross Tucker (@Scienceofsport) August 24, 2020
Oh, and this will definitely be a subject on a future episode of @sportsscipod. We just have to be patient, because I can only do it after World Rugby’s final policy is announced. Then I can talk about the whole thing, not pieces of if, and semi-transparency helps nobody. END END
Oh, and this will definitely be a subject on a future episode of @sportsscipod. We just have to be patient, because I can only do it after World Rugby's final policy is announced. Then I can talk about the whole thing, not pieces of if, and semi-transparency helps nobody. END END
— Ross Tucker (@Scienceofsport) August 24, 2020
While Tucker voice is a powerful one in rugby. Tucker, a PhD in Exercise Physiology, was named by Mail and Guardian in their list of Top 200 Influential Young South Africans, and by the Minister of Sport as one of the 100 Influential people in South African Sport.
Comments on RugbyPass
It’s impressive that we can see huge stadiums with attendance in the 40 000 to 50 000 region. It shows how popular this competition is becoming. What is even more impressive is the massive growth in broadcast viewership. The URC is one of the two best leagues in the World, the other being the Top14.
6 Go to commentsChristie is not Sottish, like the majority of the Scotland team.
2 Go to commentsHold the phone, decline over-rated. Is it a one game, dead cat bounce or the real thing? Has the Penney dropped? Stay tuned.
44 Go to commentsTotally deserved win for the Crusaders Far smarter than the Chiefs who seem to be avoiding the basics when it matters Hotham showed them what was missing and Hannah seems a real find - a tad light but that can be fixed over time
8 Go to commentsGreat insight into the performance culture with Sarries and I predict Christie will be a fixture in the Scotland team now for some time to come. However, he is slightly missing his own point around Scotland “being soft” when he cites physicality examples in defence of that slight. The issue is much closer to the example he referenced around feeling off before a game but being told “it doesn’t matter, you can still play well” by Farrell. Until Scotland can get their psyche in that square, they will carry on folding under extreme pressure…
2 Go to comments> We are having to adapt, evolve and innovate more than when we were in Super Rugby where there was only really one style that everybody had to play to gain the most success. Have = able to? Interesting what that one style might be? I thought SA sides still had bad tours now, or at least bad schedule, months away? Those extra few hours flights have to be a killer though, no surprise to see their sides doing so badly at the start of the season each year. I wouldn’t enjoy that unfairness as a supporter.
6 Go to commentsThe problem for NZ, and Aus, is they ripped up the SR model and lost a massive chunk of revenue that hasn’t been replaced. Don’t forget SA clubs went North because they were left with no choice, Argy unceremoniously binned and Japan cast adrift. Now SR wasn’t perfect, far from it, but they’ve jumped into something without an effective plan, so far, to replace what they’ve lost. The biggest revenue potential now lies in Japan but it won’t be easy or quick to unlock, they are incredibly insular in culture as a nation. In the meantime, there is a serious time bomb sitting under SH rugby and if it happens then the current financial challenges will look like a picnic. IF the Boks follow their provincial teams and head north then it’s revenue meltdown. Not guaranteed to happen but the status quo is a very odd hybrid, with the Boks pointing one way and the clubs pointing the other way. And for as long as that remains then the threat is real.
44 Go to commentsI think Etene has had some good tuition, likely while at the Warriors to be a professional that helped his rugby jump, but he was certainly thrown in the deep end way too early. Should have arguably 20 less SR caps, and therefor a way better record that he does at his age, but his development would have been fast tracked by the need to satiate his signing away from league. Again, credit to him and others that he has done it so well. Easy to fall over under that pressure in the big leagues like that but he kept at it when I myself wasn’t sure he was good enough.
1 Go to commentsAwesome story. I wonder what a bigger American (SA) scene might have mean for Brex.
1 Go to comments“Johnny McNicholl and the Crusaders” save a Penney. Who has been in camp this week and showed them how to play?
8 Go to commentsSo, reports of the Crusaders’ demise / terminal decline are perhaps just - slightly - premature/exaggerated…? 🤔 Will we see a deep-dive into that by the estimable Rugbypass scribes, and maybe one or two mea culpas? Thought not.
8 Go to comments1. The Chiefs are rudderless without DMac, which enhances his AB chances 2. Chiefs pack are powderpuffs. The hard men arent there anymore 3. They had their golden title chance last yr and wont threaten this yr. Gone in second round of playoffs.
8 Go to commentsHonestly, why did you have to publish such a foolish article the day they play us? 😂
44 Go to comments> They are not standalone entities. They are linked to an amateur association which holds the FFR licence that allows the professional side to compete in the league. That’s a great rule. This looks like the chicken or egg professional scenario. How long is it going to be before the club can break even (if that is even a thing in French rugby)? If the locals aren’t into well it would be good to se them drop to amateur level (is it that far?). Hope they can reset from this level and be more practical, there will be a time when they can rebuild (if France has there setup right).
1 Go to commentsWhat about changing the ball? To something heavier and more pointed that bounces unpredictably. Not this almost round football used these days.
35 Go to commentsThis is the problem with conservative mindsets and phycology, and homogenous sports, everybody wants to be the same, use the i-win template. Athlete wise everyone has to have muscles and work at the gym to make themselves more likely to hold on that one tackle. Do those players even wonder if they are now more likely to be tackled by that player as a result of there “work”? Really though, too many questions, Jake. Is it better Jake? Yes, because you still have that rugby of ole that you talk about. Is it at the highest International level anymore? No, but you go to your club or checkout your representative side and still engage with that ‘beautiful game’. Could you also have a bit of that at the top if coaches encouraged there team to play and incentivized players like Damian McKenzie and Ange Capuozzo? Of course we could. Sadly Rugby doesn’t, or didn’t, really know what direction to go when professionalism came. Things like the state of northern pitches didn’t help. Over the last two or three decades I feel like I’ve been fortunate to have all that Jake wants. There was International quality Super Rugby to adore, then the next level below I could watch club mates, pulling 9 to 5s, take on the countries best in representative rugby. Rugby played with flair and not too much riding on the consequences. It was beautiful. That largely still exists today, but with the world of rugby not quite getting things right, the picture is now being painted in NZ that that level of rugby is not required in the “pathway” to Super Rugby or All Black rugby. You might wonder if NZR is right and the pathway shouldn’t include the ‘amateur’, but let me tell you, even though the NPC might be made up of people still having to pull 9-5s, we know these people still have dreams to get out of that, and aren’t likely to give them. They will be lost. That will put a real strain on the concept of whether “visceral thrill, derring-do and joyful abandon” type rugby will remain under the professional level here in NZ. I think at some point that can be eroded as well. If only wanting the best athlete’s at the top level wasn’t enough to lose that, shutting off the next group, or level, or rugby players from easy access to express and showcase themselves certainly will. That all comes back around to the same question of professionalism in rugby and whether it got things right, and rugby is better now. Maybe the answer is turning into a “no”?
35 Go to commentsWow, didn’t realise there was such apathy to URC in SA, or by Champions Cup teams. Just read Nick’s article on Crusaders, are Sharks a similar circumstance? I think SA rugby has been far more balanced than NZs, no?
4 Go to commentsBut here in Australia we were told Penney was another gun kiwi coach, for the Tahs…….and yet again it turned out the kiwi coach was completely useless. Another con job on Australian rugby. As was Robbie Deans, as was Dave Rennie. Both coaches dumped from NZ and promoted to Australia as our saviour. And the Tahs lap them up knowing they are second rate and knowing that under pressure when their short comings are exposed in Australia as well, that they will fall in below the largest most powerful province and choose second rate Tah players to save their jobs. As they do and exactly as Joe Schmidt will do. Gauranteed. Schmidt was dumped by NZ too. That’s why he went overseas. That why kiwi coaches take jobs in Australia, to try and prove they are not as bad as NZ thought they were. Then when they get found out they try and ingratiate themselves to NZ again by dragging Australian teams down with ridiculous selections and game plans. NZ rugby’s biggest problem is that it can’t yet transition from MCaw Cheatism. They just don’t know how to try and win on your merits. It is still always a contest to see how much cheating you can get away with. Without a cheating genius like McCaw, they are struggling. This I think is why my wise old mate in NZ thinks Robertson will struggle. The Crusaders are the nursery of McCaw Cheatism. Sean Fitzpatrick was probably the father of it. Robertson doesn’t know anything else but other countries have worked it out.
44 Go to commentsIt could be coincidental or prescient that the All Blacks most dominant period under Steve Hansen was when the Crusaders had their least successful period under Todd Blackadder and then the positions reversed when Razor took over the Crusaders.
44 Go to commentsDefinitely sound read everybodyexpects immediate results these days, I don't think any team would travel well at all having lost three of the most important game changers in the game,compiled with the massive injury list they are now carrying, good to see a different more in depth perspective of a coaches history.
3 Go to comments