WORLD ATHLETICSMECHANICAL AIDS REVIEW PANEL

IN THE MATTER OF AN APPLICATION BY BLAKE LEEPERPANEL MEMBERSDAVID GRACE QC – CHAIR (AUSTRALIA)
RAUL CHAPADO (SPAIN)
JINARO KIBET (KENYA)DR CAROLINE NICOL (FRANCE)
ANNA RICCARDI (ITALY)DECISIONWorld Athletics has satisfied its burden of proof on the balance of probabilities
that the use of the mechanical aids by Blake Leeper in the form of passive-elastic
carbon-fibre running specific prostheses (RSPs) that give him a leg length of 104
centimetres and a standing height of 184 centimetres provides Blake Leeper withan overall competitive advantage over an athlete not using such aids, with theresult that the use by Blake Leeper of such RPSs in any World Athletics
sanctioned events is not allowed pursuant to Rule 6.3.4 of the Technical Rules ofWorld Athletics.

DATE OF DECISION

26 April 2021

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REASONS FOR DECISION
Introduction

1.

Blake Leeper is a bilateral transtibial amputee 400 metre sprinter from the UnitedStates of America.

He uses passive-elastic carbon-fibre running-specificprosthesis (RSPs) to enable him to engage in running.

2.

On 24 December 2020, he submitted an application to World Athletics to bepermitted to run on particular RSPs in the same competition as able-bodied
athletes in World Athletics sanctioned 400 metre events, including (if selected)
the 2021 Tokyo Olympic Games, and any qualification events leading up to the
Olympic Games. Subsequent to that application, by arrangements between Mr
Leeper and World Athletics, an extensive testing regime was undertaken by Mr
Leeper at the Southern Methodist University in Texas, USA, over several weeks
in February and March 2021.

The testing was conducted and regulated byProfessor Weyand who was appointed by World Athletics. Doctors Grabowski
and Beck observed the testing on behalf of Mr Leeper.

3.

In determining the application, World Athletics is required to consider its
Technical Rule 6.3.4. That Rule, as applicable to this application, provides asfollows:“For the purposes of this Rule, the following examples shall be considered assistanceand are therefore not allowed;
6.3.4

4.

The use of any mechanical aid unless on the balance of probabilities the use ofan aid would not provide them with an overall competitive advantage over anathlete not using such aid”.

The Mechanical Aids Review Panel (“the Panel”) was established by the World
Athletics Council in January 2021. The Panel reports to the Council. The role of
the Panel is to consider applications and determine pursuant to Rule 6.3.4 of theTechnical Rules, whether any mechanical aids proposed to be used by an athlete
provide him or her with a competitive advantage. The Terms of Reference of the
Panel include, inter alia, the following:2

(a)the Chairperson and the pool of persons who may sit on a Panel shall be
appointed by the President and Chief Executive Officer of World Athletics
under delegated authority from the Council;(b)

the Panel shall consider applications in a timely and efficient manner andmake a decision in respect of the application;(c)the Panel shall liaise, coordinate with and attain advice from other World
Athletics Commissions, Working Groups and Departments, whererequired, and/or other relevant experts on specific issues concerning anapplication;(d)the Panel shall act at all times for the sole purpose of conducting a full andfair assessment of every application submitted and review eachapplication fairly and impartially, and base its decision solely on its
assessment of the evidence before it;(e)the Panel shall issue written decisions with reasons and may publish thedecision or a summary of it.

5.

On 3 July 2019, Mr Leeper applied to the IAAF (the former name of World
Athletics) for a ruling that the RSPs that he then used were allowable under theRules. On 18 February 2020, the application was denied on the basis that Mr
Leeper had not met his burden of proof to show on the balance of probabilities
that his use of the RSPs would not provide him with an overall competitive
advantage over an athlete not using such prostheses. Mr Leeper appealed to
the Court of Arbitration for Sport (CAS).

6.

A two day hearing before the CAS by video-link occurred on 13 and 15 July
2020. The decision has been published under the citation CAS/2020/A/6807
Blake Leeper v International Association of Athletics Federations. The decision
is dated 23 October 2020. The CAS decided that Technical Rule 6.3.4 (cited3

above) was unlawful and invalid insofar as it placed the burden of proof upon an
athlete desiring to use a mechanical aid to establish that the use of themechanical aid will not provide the athlete with an overall competitive advantage
over an athlete not using such an aid. However, the CAS found that the IAAF
had established on the balance of probabilities that the particular RSPs used by
Mr Leeper gave him an overall competitive advantage over an athlete not using
such a mechanical aid and accordingly, Mr Leeper was not permitted to use
those specific RSPs in the Olympic Games or World Athletics Series
competitions. In relation to the Technical Rule itself, as a result of the CAS
ruling, World Athletics now bears the onus of proof as outlined above.

7.

The CAS Award is lengthy and details the extensive evidence and arguments
considered by the CAS.

The Panel has read carefully the CAS Award.

Itcontains detailed reasons for its decision. The Panel is entitled, and does, have
due regard for those reasons and to the analysis undertaken in respect of a notdissimilar factual and expert opinion substratum. A number of the findings offacts made by the CAS are relevant to this new application by Mr Leeper andreference will be made to them during the course of these Reasons. The Panelhas considered carefully all the expert reports and written submissions submitted
on behalf of Mr Leeper and on behalf of World Athletics. In these Reasons,however, the Panel will only refer to those parts of the reports and submissions it
considers necessary to explain its reasoning. The Panel has based its decision
solely on its assessment of the evidence before it.

Background

8.

Mr Leeper’s career as a competitive sprinter is set out in the CAS decision atparagraphs 122 – 128. It is evident that he has achieved considerable successas an athlete notwithstanding his disability. He is a multiple medallist in World
Para-Athletics competitions.

9.

Before the CAS, Mr Leeper relied primarily upon the expert evidence from
Doctors Grabowski, Taboga, Beck and Herr.

Mr Leeper relies upon a4

Declaration from Dr. Graboski dated 24 December 2020 and updated reports
from Doctors Grabowski, Taboga and Beck in support of this new application.
World Athletics, at the CAS hearing, relied upon the expert evidence ofProfessors Weyand and Bundle and Doctors Tweedy, Connick and Beckman.
The same experts (with the exception of Dr. Herr) are now relied upon by each of
Mr Leeper and World Athletics in relation to this new application and they haveeach produced (albeit jointly in all cases) further expert reports. Each of theexperts are eminent in their fields of expertise with vast experience.

10.

The difference in this new application by Mr Leeper is that he now seeks
approval to use RSPs (of the same type) that are set so that his standing heightis approximately 184 centimetres which is approximately 5 centimetres less than
the standing height of 189.2 centimetres for the RSPs that were the subject of
the application ruled upon by the CAS.

11.

The question for this Panel to consider is whether World Athletics can establish
on the balance of probabilities that the use of the new RSPs by Mr Leeper would
provide him with an overall competitive advantage over an athlete not using suchaids.

The present application

12.

As stated above, the intention of Mr Leeper is to use new RSPs that are set at ashorter height than the RSPs he previously used. The respective RSPs are of
the same type, but the new RSPs are set so that they are approximately 5centimetres lower than the RSPs with which Mr Leeper had previously run.

13.

The Maximum Allowable Standing Height (MASH) rule for disabled athletes wasestablished by the International Paralympic Committee and World Para Athletics
to prevent a disabled athlete from using a prosthetic limb that results in that
athlete being able to compete at a total height which is greater than the
maximum possible height that athlete would have been if they had fully intact
biological limbs. The rule reflects the fact that amongst able-bodied individuals
5there is a general correlation between the length of an individual’s lower limbs
and the length of other parts of their body. Although the correlation is not exact,
it has been held to be sufficiently strong and established to enable scientists tocalculate the maximum possible height a person could be based upon the sizeand dimensions of certain parts of their body. At paragraphs 378 – 385 of theCAS decision, the MASH rule was considered and found to provide “an objective
and reliable indication of Mr Leeper’s likely maximum height if he had intact
biological legs”. Before the CAS it was not in dispute that if Mr Leeper was
required to comply with the MASH rule, then he would not be permitted to run ata height above 174.4 centimetres. The CAS found that since Mr Leeper’s RSPs
enabled “him to run at a height which is significantly taller than his MASH, Mr
Leeper is indeed running unnaturally tall. In short, he is running at a height which
is significantly greater than the height that he would run at if he had intact
biological legs” (at paragraph 385).

14.

In the written application filed on his behalf, Mr Leeper submits that:(i)the MASH standards are racially discriminatory, as they are not based on
any body proportion data from Black athletes of African descent;(ii)

published data demonstrates that Black athletes of African descent have
longer legs than Caucasian athletes in proportion to their torsos; and(iii)

there is no basis for World Athletics to apply the MASH standards to meetits burden to prove that Mr Leeper has any overall competitive advantage
over able-bodied athletes running on his prostheses at this new height.

15.

During the CAS hearing, there was considerable analysis of the ambit andmeaning of Technical Rule 6.3.4. This Panel is of the opinion that the conclusion
reached by the CAS is a proper basis upon which this Panel shall consider thisfresh application by Mr Leeper. At paragraph 310, the CAS said:

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“Having regard to these factors, the Panel concludes that the only logical, principled andworkable construction of the Rule is one that, in the case of disabled athletes who use amechanical aid to overcome a disability, requires the comparison to be undertaken
between the athlete’s athletic performance when using the mechanical aid and their likely
athletic performance had they not had the disability which necessitates the use of that
aid. A disabled athlete who uses a mechanical aid which does no more than offset thedisadvantage caused by their disability cannot be said to have an ‘overall competitive
advantage’ over a non-disabled athlete who is not using such an aid. In such a case, themechanical aid does no more than counteract a disadvantage which the able-bodied
athlete does not share. Conversely, a disabled athlete who uses a mechanical aid which
does not merely offset the disadvantage caused by their disability, but enables the athlete
to achieve better overall performances than they would have achieved had they not hadthat disability, can be said to have an ‘overall competitive advantage’.”16.

The CAS went on to determine that the question about whether a particulardisabled athlete derives an “overall competitive advantage” can only beanswered by comparing the actual performance by the athlete while running with
their disability and their mechanical aid and the performance they would
hypothetically have been capable of achieving if they were running without that
disability and without that aid.

17.

In the opinion of the Panel, the comparative analysis undertaken by the CAS atparagraphs 363 – 390 is the same type of analysis that this Panel has toundertake, based upon the new reports that have been provided, the new
evidence in the form of the tests conducted upon Mr Leeper in running trials heldin Texas in February and March 2021 and our own consideration of all the
documentary materials with which we have been provided.

Analysis18.

The primary focus of the submissions made on behalf of Mr Leeper concerns theapplicability of the MASH standards to him.

The contention that the MASH

standards are racially discriminatory as they are not based on any body of
proportional data from Black athletes of African descent is not a matter that canbe determined by this Panel. As outlined above, our Terms of Reference dictatethat our only role is to consider whether or not World Athletics has met its burden
imposed by Rule 6.3.4. The contention that the published data demonstrates
that Black athletes of African descent have longer legs than Caucasian athletes7

in proportion to their torsos is a particular of the argument made by Mr Leeperthat there is no basis for World Athletics to apply the MASH standards to meet its
burden to prove that Mr Leeper has any overall competitive advantage.

19.

In order to determine the ultimate question as to whether World Athletics has met
its burden of establishing an “overall competitive advantage” there are a numberof intermediate questions that need to be answered:

(a)
(b)
(c)
(d)

20.

does the MASH rule have an application outside the context of regulating
para-athletics?
does the MASH rule have any application to Black athletes?
does Mr Leeper run unnaturally tall in using his new RSPs which give him
a standing height of 184 centimetres?
does the height of Mr Leeper’s RSPs result in Mr Leeper running faster inthe 400 metre event than would otherwise be the case?

The Panel has adopted the above questions as part of a stepped and logicalprocess to determine the ultimate question.

Does the MASH Rule have an application outside the context of regulating paraathletics?

21.

The Panel has read carefully the Reasons for Decision of the CAS in relation tothis question. Mr Leeper effectively maintains that the MASH rule does not apply
to him because:(a)it has no application outside the context of regulating para-athletics;(b)

able-bodied athletes are not subject to any height limits and the fact thatthe height that Mr Leeper would run at on his new prostheses is very
comparable to the standing height of other elite able-bodied 400 metre
runners of African descent means that the new prostheses would not
result in him enjoying an unfair height advantage when competing against
such athletes.

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22.

It is true that the MASH rule does not govern eligibility to compete in World
Athletics sanctioned events. For able-bodied athletes eligibility is not determinedby height, strength, leg speed or similar personal attributes or characteristics.
However, we adopt the same reasoning process as adopted by the CAS (atparagraph 381) to the effect that the MASH rule is not irrelevant to ourassessment and it provides an objective and reliable indication of Mr Leeper’s
likely maximum height if he had intact biological legs.

23.

In its decision (at paragraph 383) the CAS said the following:“An able- bodied athlete cannot, of course, change the length or proportions of their legs.
In contrast, an athlete with one or two missing biological limbs can determine the lengthand proportions of the prosthetic ... limb which they use in place of the missing biologicallimb. Amputee athletes are therefore able to determine the height at which they compete
in a way that non- amputee athletes are not.”24.

The reason for such a rule in respect of amputee athletes competing in para
athletic events is clear. It is to prevent disabled athletes from over- compensating
for the absence of a missing limb. Issues of fairness obviously are paramount. In
respect of the application of Rule 6.3.4 issues of fairness are at the root of thereason for the imposition of the rule.

25.

The panel is therefore of the opinion that the MASH rule does have anapplication outside the context of regulating para- athletics.

Does the MASH rule have any application to black athletes?

26.

This is an issue of great contention between the respective experts.

27.

In the application of Mr Leeper dated 24 December 2020, a Declaration of Dr.
Alena Grabowski was attached. The declaration reviewed existing and historicalstudies on body proportionality regarding black persons from Africa or of African
descent. Dr. Grabowski asserted, based upon those studies, that applying the
MASH rule to Mr Leeper was scientifically invalid and racially discriminatory “asthe data underlying the MASH rule are severely limited because they are not9based on any data from Black persons from Africa or of African descent” (atparagraph 4).

28.

Dr. Grabowski relied upon the study by Connick et al in 2015 and quoted fromthat paper a statement to the effect that it was not known if the equations
employed were predictive of the stature in other populations not studied (eg.
Black persons from Africa or of African descent).

The MASH formula predicts

the height double-amputees would be if their legs were intact based on an
equation that uses the lengths of their thigh, upper arm, forearm and sittingheight and the giving of different ratings to each of those measurements, andthen adding an error factor of 1.91 centimetres to cover normal variation. The
original study was undertaken by Canda in 2009 but relied upon measurementsfrom Caucasian athletes only. In Connick’s study he showed that the formula
was equally accurate for Japanese subjects despite them having different body
proportions to Caucasians.

29.

In 1964, Tanner published a study describing the physique of a considerable
number of track and field athletes who competed at the 1958 British Empire andCommonwealth Games and at the 1960 Olympic Games in Rome. That study
showed that on average black people have different body proportions to white
people. On average they have longer legs, shorter trunks (and therefore shorter
sitting heights) and longer arms.

30.

Dr. Grabowski emphasised in her Declaration that the Canda and Connick
studies wholly ignored in their study populations black persons from Africa orfrom African descent. She also relied upon the statement by Connick that the
MASH regulations would be strengthened with an internationally representative
sample.

Dr. Grabowski referred in some detail to Tanner’s study.

Sheemphasised that the differences in the various measurements between white andblack athletes were marked. The development of the MASH formula relied upon
the various ratios that he employed and were different depending upon whether
the athlete was white or black, according to Dr. Grabowski.
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31.

In their joint expert report filed on 16 March 2021, Professors Weyand andBundle agreed that Tanner and others “have shown that on average black people
have different body proportions to white people: on average, they have longer
legs, shorter trunks (and therefore shorter sitting heights), and longer arms” (seeparagraph 5.2). They add however that “these comparisons do not address thecritical issue here, because the formula is based on a combination of thosemeasurements, each weighted between 99.8% and 82% of their original length.
As a result, the fact that the legs are longer is offset by the fact that the trunk isshorter, and by the different weightings given to each measurement. To answer
the question directly, we took the underlying data collected by Tanner…and fed
the data into the Canda model. We found that the model predicts standing height
just as accurately for black people as it does for white people. In fact, it veryslightly over-estimates the standing height of black people. Because the Tanner
data relates to Olympic athletes spanning in height from 5 foot to well over 6 foot,this analysis provides strong and robust evidence that the height that the MASH
formula predicts for Mr Leeper (174 centimetres) is valid. These data indicatethat Mr Leeper’s pre-2021 RSPs meant his legs were 15cm longer than theywould be if they were intact, and his current RSPs which are 5 centimetresshorter make his legs 10cm longer than they would be if they were intact”.

32.

In an expert report of Doctors Grabowski, Beck and Taboga filed in response tothat report of Professors Weyand and Bundle, and dated 26 March 2021, theexperts criticise the Weyand/Bundle report. They claim that the application of the
MASH formula to black athletes of African descent is deeply flawed. Reliance forthis conclusion was based upon the absence of any study conducted on thevalidity of the MASH criteria using athletes of African heritage and the absence of
any MASH data collected from black athletes. Criticism was made upon the use
by Professors Weyand/Bundle of photos from the Tanner study which were over
60 years old, together with the fact that the Tanner photos were 2D and humans
are 3D which makes the measurements inherently incorrect because they were
not taken along the axis of the limb segment. The result was that the bodysegment dimensions reported in the Weyand/Bundle report are not measured but
estimated based on multiple inaccurate 2D measurements, it was claimed.
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There were a number of other criticisms made of the Weyand/Bundle report, anumber of which will be discussed later in these Reasons.

33.

In their expert report dated 16 March 2021, Doctors Tweedy, Connick andBeckman, all of the University of Queensland, Australia (UQ report), outline thehistory of the development of the MASH rule. They state, at paragraph 28:“however, because Canda’s equations were derived from a Spanish population, it was
not known if the equations work with people from different geographic locations, orwhether the equations provided a more accurate estimate of standing height than theupper body method or the Contini method [being the use of an average of the standingheight estimations from the ratios obtained by the comparison of limb and other bodylengths]. Therefore we conducted a study, published in 2015 (Connick)), that compared
the validity of the upper body method, the Contini ratios, and the Canda equations for
estimating standing height. We deliberately drew samples from two locations that were
geographically distant from Spain – Japan, which is approximately 10,600 km from Spain,
and Australia which is 15,700 km from Spain”.

34.

The justification, in part, for choosing samples from locations that were so
geographically distant from where Canda’s sample was taken was that theamount of genetic variability was relatively large. As a result of the Connick
study the International Paralympic Committee and World Para Athletics changed
the MASH rule in 2018 and based it on the Canda equations. In their report UQ
sets out the new MASH rule including the relevant body segment measurements
and the formula that should be applied to establish MASH for a male athlete withthe disability of a below-knee limb deficiency, as is the case with Mr Leeper.
The authors conclude that based upon the quality and size of Dr. Canda’s
original study and the authors’ own study, that they were confident that thecurrent formula used in the MASH rule would not lead to “significantly different
results in different populations, and in particular, in a black population”(paragraph 33).

35.

As to the claim that the use and application of the equations in the MASH rule
are without scientific basis, the authors claim that the scientific basis“underpinning the validity of the formula in different populations is very sound” (atparagraph 33.5).

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36.

As a result of the comments made in the expert reports of Doctors Grabowski,
Beck and Taboga dated 26 March 2021, Professors Weyand and Bundle
prepared an expert report in response, dated 5 April 2021, as did UQ in a
separate report dated 5 April 2021.

37.

In the Weyand/Bundle response Report, the experts state that the data from theTanner report provided an opportunity to use published data to evaluate whether
the MASH formula can appropriately be applied to male black athletes. They
state (at Section B, page 1) that:“Dr. Grabowski’s Declaration included with Mr Leeper’s application relies
heavily on the Tanner data as evidence of different body proportions,specifically longer limb segments and shorter sitting heights in black
compared to white athletes of the same stature…With the acceptance of
this published data therefore established, we use the Tanner source toevaluate the MASH formula.”

38.

In relation to the criticism in the Grabowski Response Report dated 26 March
2021 of the use of 2D images, they respond that the process of extracting
accurate length measures from photographs has been common practise innumerous scientific disciplines for over a century.

A number of publishedscientific articles support the application of such techniques which are applied
today. Further, in the Grabowski response Report itself a version of this approachoccurred. For the reasons stated, including the fact that scientific protocols were
followed in relation to collection and analysis, Professors Weyand and Bundle
maintain that the analysis of the photographic plates from 1960 taken by Tanner
is just as valid as if they had obtained similar photographs from Olympians in
2021.

39.

The Professors accepted that measuring anatomical segments from photographs
is not as precise as physically measuring the subjects in person, however the
MASH estimates using the photographic analysis when applied to the 100
Olympians from the Tanner study had an accuracy of 2.8 centimetres that wasclose to the accuracy of the gold standard of 2.5 centimetres suggested by
Connick in his study in 2015. Importantly the analysis of the Tanner photographs13indicated that “the MASH predictions for black and Asian athletes have similarlevels of accuracy to the whole, and are not systematically over - or underestimated , as would be the case if MASH was inappropriate for a particularracial group” (page 2). They maintain that “because the Canda method uses amore thorough measure of the body's limb segments to achieve accuracy, MASH
appears to work equally well for different racial groups” (page 3).

40.

In their response Report dated 5 April 2021, the UQ experts claim (at paragraph13) that there is absolutely no evidence that the MASH formula is not valid:“While it is true that black people may have shorter trunks and longer limbs than white
people, it does not follow that the formula will not be valid because...The Canda formula
uses direct measures of four body segments to predict height. This means that if any
person- black or white- has a relatively shorter trunk and longer limbs, any disadvantage
resulting from a shorter trunk will be offset by relatively longer measures for his upper
arm, his forearm and his thigh ... the magnitude of the differences that have beenreported are so small they underscore the consistency and homogeneity between racial
groups rather than amplifying them ... The difference [between black and white people] insitting height is 1 cm… and the difference in leg length is 3.2 cm... Mr Leeper is seeking
permission to use prosthetics that are 10.98 cm longer than predicted - more than fivetimes the size of the difference between black athletes and white athletes reported by
Tanner ... The marginal differences that may or may not exist between black and white
populations after application of the Canda formula would be mitigated by the 1.91 cm
pure error addition in the MASH formula , which is added to the predicted height of eachathlete to account for any possible natural biological variation”.

41.

The UQ experts further rely upon findings of the American Association for
Physical Anthropology, the world's leading professional organisation for physicalanthropologists.

Amongst the findings were that natural biological variation

between individual human beings, including the proportionality of body segment
lengths, is driven by variations in genetic makeup and that race does not provide
an accurate representation of human biological variation. Differences andvariations exist with and among populations throughout the world but thosevariations do not align with socially defined racial groups such as whites andblacks.

42.

The UQ experts maintain that the Canda equations provided the most valid
estimations of standing height across the Japanese and Australian samples the
subject of their rigorous study. They found that the error of the estimated staturein the Australian sample was not significantly different from that in the Japanese14

sample despite the fact that the Japanese males had significantly shorter thighlength compared to the Australian males and were significantly shorter instanding height:“That the two populations were distinct was particularly important to demonstrate that theequations could be used to generalise across populations, including people with a wide
range of body proportions” (paragraph 14.4 ).

43.

The UQ experts respond further to other criticisms made in the Grabowski report
including the claim that there is considerable measurement error in the Mashequation by the under- predicting of heights. This is refuted in paragraphs 15 and
16 of the UQ response report by the citation of figures that appear to reveal
flawed analysis in the Grabowski report. The UQ experts go so far as to say that
there is more likelihood that Mr Leeper would be advantaged by the MASH rulethan the likelihood that he would be disadvantaged. In summary the UQ experts
endorse the conclusions of Professors Weyand and Bundle that the MASH
formula is a valid means of predicting height for a black population generally andfor Mr Leeper specifically.

44.

This Panel concludes that the weight of rational scientific opinion is to the effectthat the MASH rule does have application to black athletes. We so conclude
based upon the rationale expressed in the various reports to which reference has
been made. We have carefully considered all the competing arguments and are
confident that there is a scientifically proved basis upon which the MASH rule has
the asserted application.

Does Mr Leeper run unnaturally tall in using his new RSPs which give him astanding height of 184 centimetres?

45.

In her Declaration dated 24 December 2020 Dr Grabowski expressed the opinion
that it was “scientifically unsound to state that Mr Leeper runs at an ‘unnaturally
tall’ height based on the MASH rules, as the MASH rules upon which that
conclusion is based do not take into account the limb proportions specific toBlack persons from Africa or of African descent “. That statement is consistent15

with the submissions made on behalf of Mr Leeper as presented to this panel.
There was no real challenge to the proposition that if MASH applied the correct
MASH was 174.4 centimetres.

46.

At the CAS hearing it was not in dispute that, were Mr Leeper required to comply
with the MASH rule, he would not be permitted to run at a height greater than
174.4 centimetres. At the tests conducted at the Southern Methodist University
in February and March 2021 Mr Leeper’s standing height with his new RSPs wasmeasured at 184 centimetres with a leg length of 104 centimetres.

47.

The difference between the MASH and his standing height is thus 9.6
centimetres. The only conclusion that is open is that Mr Leeper is running
unnaturally tall in using his new RSPs.

Does the height of Mr Leeper’s RSPs result in Mr Leeper running faster in the 400
metre event than would otherwise be the case?

48.

In the joint expert report of Doctors Grabowski , Beck and Taboga dated 26
March 2021, extensive criticisms were made of the testing of Mr Leeper with his
new RSPs by Professors Weyand and Bundle at the Southern Methodist
University in February and March 2021. The criticisms were based upon what
was alleged to have been scientifically unsound and deeply flawed testingprocedures.

At the heart of the criticisms was the allegation that Professor

Weyand’s conduct and conclusions were a product of self interest in protecting
the credibility of his prior testimony before the CAS and contrary to his publicisedscientific theory on prosthesis length. It was alleged that the testing was revisedin the middle of the test regime and terminated early at times so as to prejudice
Mr Leeper. It was further claimed that the data collected contradicted Professor
Weyand’s claim that Mr Leeper ran slower with his shorter prostheses and that
active steps were taken to prevent Mr Leeper from recording valid performances.
Most alarmingly, it was asserted (at page 6) that Professor Weyand repeatedly
revised the testing throughout the protocol and that “is an archetypal example ofa test that has a potential for ‘rigging’ in search of a predetermined outcome“.
16These claims were extraordinary. They amounted to allegations of professional
misconduct.

49.

The claims were entirely and effectively refuted by Professors Weyand andBundle. Detailed explanations in response to the allegations were made in the
response Report dated 5 April 2021. Explanations for what were said to be
defects in the testing procedures were discussed in detail. Far from revealingthat there was any basis for the claims made against them, Professors Weyand
and Bundle in their response present an overwhelming case to the contrary.
Most, if not all, of the allegations probably would not have been made if Doctors
Grabowski, Beck and Taboga had contacted Professors Weyand and Bundle
before written reports were completed and any concerns discussed. Moreover,as Doctors Grabowski and Beck were present, they were in a position to convey
any concerns after the testing for a particular day had ended even if they were
not permitted to comment during the testing (as was the case pursuant to thetesting protocol), but they failed to do so.

50.

The essence of the opinion in respect of this question, in the joint Grabowski
report dated 26 March 2021, is that there is no support for the conclusion thatrunning taller enables Mr Leeper to run the 400 metres faster than would
otherwise be the case. Before the CAS and before this panel Mr Leeper relies
upon a paper published by the same experts in 2020 titled ”Prosthetic shape, but
not stiffness or height, affects the maximum speed of sprinters with bilateraltranstibial amputations” (the Taboga paper).

51.

The CAS found that the paper does not provide reliable support for the
proposition advanced by Mr Leeper. The principal reasons for that conclusion(which has been reached also by this Panel), is that the paper was based ondata from a sample size of just five athletes and statistically meaningfulconclusions from a sample population as small as that are difficult to draw.
Further there was no statistically significant relationship between the length of the
RSPs of the athletes and their running speeds and each of the participants
underwent a significant number of maximal speed tests in a period of just 10 - 1117

days which had the effect of undermining the results due to insufficient rest time.
This led the CAS to the conclusion that the reliability of the data generated by thestudy is therefore open to question.

This Panel has reached the sameconclusion. Still further, the study involved changing not just the height of the
RSPs but also changing the model and stiffness of them. Therefore it would benecessary to reliably exclude any possible effects which arise from thesedifferent models and different levels of stiffness to draw any reliable conclusions.
Importantly some of the results detailed in the paper were in fact consistent withthe proposition that increases in prosthetic height causes increases in runningspeed. The results did not all point in the one direction. The CAS accepted theobservation of the UQ experts to the effect that upon the maximum speed
attained by each of the five subjects while using their usual model of RSP's at theusual stiffness, all but one of the five subjects achieved their maximum velocity ateither +2 centimetres or +4 centimetres, suggesting that increasing prosthetic
height may cause an increase in maximum speed (see paragraph 387). A further
reason given by the CAS for not relying on the paper was that a number ofscientists had written to the Journal that had published the paper asking for it tobe retracted due to what the scientists had regarded as a fundamental flaws in
the paper's methodology and analysis. This followed the rejection for publicationof the paper by a number of journals. This led the CAS to have further concerns
regarding the reliability of the conclusions in the paper. This Panel finds the UQ
Response Report dated 5 April 2021 to be persuasive in relation to theconclusions regarding the flaws in the Taboga paper.

52.

In the Grabowski report, the authors rely upon the Taboga paper as providing asound basis for the conclusion that there is no relationship between prosthetic
height and maximum running velocity. Indeed based upon the results of tests on
two athletes taller prosthetic heights of up to 16 centimetres reduced maximum
velocity. After conducting the experiments that formed the basis of the Taboga
report, the analysis revealed no association between prosthetic height andrunning speed. If this is indeed the opinion of the experts a question could be
asked as to why there is an insistence upon the use of the current RSPs when18

height is not a factor? Such an approach would have obviated the need for thisapplication before this panel.

53.

The expert reports of Professors Weyand/Bundle and those of the UQ experts
are to the contrary. They all conclude that there is a direct relationship between
leg length and maximum sprint running speed.

The reason for this is theiropinion that there is a close correlation between an athlete’s leg length and their
ground contact length and increasing the size of a prosthetic limb beyond normal
anatomical proportions increases ground contact length.

Foot-ground contact

times are closely linked to sprint running performance due to mechanical andbiological reasons. As stated in the Weyand/Bundle report dated 16 March 2021
(at page 6):“The data available on male runners, including Mr Leeper, indicate that top speed contact
lengths are roughly equal to the length of the leg. Thus, a simple lengthening of the RSPs
results in a direct increase in the length of contact during running. And lengthening the
distance travelled within the same foot- ground contact time augments the top speed...”54.

In the tests conducted at the Southern Methodist University in February andMarch 2021, Mr Leeper’s maximum speed obtained was 10.9 m/s in accordancewith the tests conducted. This is disputed by the Grabowski report which claims
that a speed of 11.1 m/s was reached. The Panel accepts the Weyand/Bundle
response that 10.9 m/s is the validated top speed and the explanation for it.
Regardless, the top speed using 5 centimetre taller prostheses in tests
conducted in Colorado in 2018 was 11.4 m/s. In their first report dated 16 March
2021, the Professors conclude that this was the expected reduction in top speed
due to the reduction in RSP length. It would be further anticipated that the top
speed able to be achieved on MASH-compliant prosthetics would be 9.9 m/s. In
the 2018 Colorado tests Mr Leeper used RSPs that gave him a leg length of 109
centimetres.

The maximum speed reached of 11.4 m/s was extrapolated toprovide a 6.8 second performance benefit in the 400 metres. By reducing thelength of his RSPs by 5 centimetres, he reduced his leg length to 104
centimetres, and reduced his maximum speed to 10.9 m/s which equates to anincrease of approximately 2.1 seconds over 400 metres. This is still much faster19

than he would achieve if he was MASH compliant. His current benefit is 4.7
seconds over 400 metres.

55.

In the UQ report the experts conduct a detailed analysis that results in the
conclusion that longer RSPs permit faster maximum running speeds. Detailed
comparisons which were reflected in various tables and diagrams together withdetailed descriptions and analyses of the results revealed in these tables anddiagrams have satisfied the Panel that there is a direct relationship between leg
length and running speed and that therefore the height of Mr Leeper’s RSPs
result in him running faster in the 400 metre event than would otherwise be thecase. This was also the conclusion reached by the CAS.

Do the RSPs intended to be used by Blake Leeper provide him with an overall
competitive advantage over an athlete not using such aids?

56.

The Panel is conscious of the fact that an athlete using RSPs suffers
disadvantages in acceleration out of the starting blocks and in the first part of any
400 metre race and may also suffer a small disadvantage in bend running,although this last point was the subject of disagreement amongst the respective
experts. What is clear, however, is that once the acceleration phase is complete
and the athlete is able to run freely, the speed able to be achieved is substantial.
A viewing of the video of Mr Leeper’s race in Prague, Czech Republic, in 2018
when he achieved his personal best time (freely available on the internet) reveals
how Mr Leeper actually runs in competition.

He deserves full credit for the

obvious fitness and expertise shown. Undoubtedly, he has been engaged formany years in extensive training.

57.

In any comparison between his performances and that of able-bodied athletes,
some further considerations, not considered in any or great detail in the present
reports by the experts, are worthy of mention in our opinion. Firstly, the effect of
fatigue. It appears that Mr Leeper negatively splits 400 metre races. This means
his second 200 metres is faster than his first. This is exactly the reverse of what
happens to world class able- bodied 400 metre runners including the world20

record holder (and by a sizeable margin). The CAS did hear evidence of this.
Secondly, the effect of flexion in the prostheses. Does greater flexion promoteincreased performance or does it do the reverse? Thirdly, in any comparison ofstanding height should allowance be made for the fact that an able-bodied
athlete is permitted to wear a running shoe in 400 metre events that have a 2 cm
thick sole thus giving that athlete a 2 cm height increase?

If this is a valid

consideration, then the difference between Mr Leeper’s current standing height of
184 cm and his MASH may be reduced for comparison purposes with ablebodied athletes.

But even so, the increase in height over the MASH is still

significant in Mr Leeper’s case.

58.

Whatever may be the answer to the above questions we are satisfied that on all
the evidence presented to this Panel, the present RSPs used by Mr Leeper doprovide him with an overall competitive advantage and that therefore he is not
permitted to use the current RSPs as mechanical aids in any World Athletics
sanctioned events as such use is in contravention of Technical Rule 6.3.4.
Dated this 26th day of April 2021

David Grace QC
Chair, World Athletics Mechanical Aids Review Panel

RAUL CHAPADO (Panel Member)
JINARO KIBET (Panel Member)
DR CAROLINE NICOL (Panel Member)
ANNA RICCARDI (Panel Member)21