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Science & Sports (2012) 27, e55e61

Disponible en ligne sur

www.sciencedirect.com

ORIGINAL ARTICLE

Antero-posterior position of the cleatfor road cyclingPositio

J. Ram

Centro Doc

Received 28Available on

KEYWOEnglish: Cycling;Foot;Lower li

MOTS CCale ;Vlo ;Pied ;Membres

CorrespoE-mail a

0765-1597/$doi:10.1016n antro-postrieure de la cale pour le cyclisme sur route

os Ortega , P.V. Munuera, G. Domnguez

ente de Fisioterapia y Podologa, Department of Podiatry, University of Seville, C/Avicena s/n, 41009 Sevilla, Spain

September 2010; accepted 7 December 2011line 20 January 2012

RDScleat;

mb

SummaryObjective. This work aims at determining the antero-posterior position of the cleat based onvarious morphological characteristics of the cyclists lower limb.Method. Two tests were used to quantify this position: a photograph-based one and aradiograph-based one. Both, the photograph and the radiograph were digitalized to enablemeasurements by means of the software AutoCAD 2006. Two linear regression models wereconstructed from the variables cleat/rst metatarsal distance and tip/cleat distance, whichwere invalidated by the low squared-R coefcient value (0.106 and 0.057, respectively).Results. Participants presented almost constant values of 3.6 0.8 cm for the cleat/rstmetatarsal distance and 0.43 for the tip/cleat distance. As the distance from the base ofthe cleat to the pedal spindle is 3.6 cm, it may be stated that the pedal spindle may coincidewith the head of the rst metatarsal by positioning the base of the cleat at 43% of the lengthof the shoe measured from its distal end. 2011 Elsevier Masson SAS. All rights reserved.

LS

infrieurs

RsumObjectif. Ce travail vise dterminer la position antro-postrieure de la cale sur la base dediverses caractristiques morphologiques des membres infrieurs du cycliste.Mthode. Deux essais ont t utiliss pour quantier cette position : une photo et une radio-graphie de base. Les deux, la photographie et la radiographie ont t numrises an depermettre des mesures au moyen du logiciel AutoCAD 2006. Deux modles de rgressionlinaire ont t construits partir des variables distance cale/premier mtatarsien et dis-tance pointe/cale, qui ont t invalides par la faible du coefcient R (respectivement 0,106 et0,057).

nding author.ddress: jrortega@us.es (J. Ramos Ortega).

see front matter 2011 Elsevier Masson SAS. All rights reserved./j.scispo.2011.12.004

e56 J. Ramos Ortega et al.

Rsultats. Les participants ont prsent des valeurs quasi-constantes de 3,6 0,8 cm pour ladistance cale/premier mtatarsien et de 0,43 pour la distance pointe/cale. Comme la distancede la base de la cale laxe de la pdale est de 3,6 cm, on peut dire que la pdale de brochepeut concider avec la tte du premier mtatarsien par le positionnement de la base de la cale

esus rs

1. Introd

The most cthe knee, s[1,2]. Cycliproblems abecause of[3]. Such indown stairsaling. As fafew data rdiscomfortinjury due or latero-mstudies aimthe elemebetween cof the saddare the moedge, thereon the shoalignmentsinto accouna circular pthe shoe/pthe two parlimb does nforces genthat are noAn incorreposterior f

Shoe/pemission of tso that thetant factorcaused by the authorslongitudinaSome authcidence ofmetatarsalbe with the

This wo

to analyzaccordinis, metafrom thethe distaof the cl

to detertances) i

onstrtion . Thehe cables

tho

rgetplessay (mted

numed vg beusly)dataticippant4 1r, Nritteprovsity ust thero fepantte eanu eblemerenple,

thislowe

samed o

inchan atism

sufuringk, ters

varand 20 d 43 % de la longueur de la chaussure m 2011 Elsevier Masson SAS. Tous droit

uction

ommon injuries in the cyclist are those affectingome 25% of all the non-traumatic injuries sufferedsts of any category might be affected, but thesere most frequent among those of a high level,

the substantial distances they cover in trainingjuries can range from slight discomfort on going

or after a long ride, to the impossibility of ped-r as the authors are concerned, there have beenecorded during recent years on the incidence of

in cyclists knees. The most frequent types ofto overloading in cycling result in femoropatellaredial pain in the knee joint [1,35]. Differented at preventing these problems have analyzednts giving the most exact alignment in the tycle and cyclist for each rider [6,7]. The heightle and handlebars, and the length of the crankst common but, according to the authors knowl-

is no research on the exact position of the cleate. Cycling injuries may also be the result of mis-

between cyclist and bicycle. It must be takent that the pedal restricts the foot movement toattern in the sagittal plane of motion, and thatedal xing systems do not allow movements ofts in the frontal or transverse planes. If the lowerot describe a normal trajectory during pedaling,erated in pedaling may add loads to the jointst associated to the propulsion of the cycle [8].

ct antero-posterior position affects the antero-orces of the knee [911].dal interaction is crucial for an effective trans-he forces generated by the cyclist to the bicycle,

alignment of these parts is considered an impor- in the management and treatment of injuriesoverloading of the knee [12]. Currently, as far as

are concerned, there is no consensus on the ideall position of the cleat to prevent these injuries.ors refer to an adjustment based on the coin-

the pedal spindle with the head of the second [9,11,13,14], whereas others claim that it should

head of the rst metatarsal [7,15,16].rk is designed with the following aims:

e the exact position of the cleat for each cyclist,g to some variables measured on their feet (thattarsal index, forefoot adduction, the distance

to cposiblesof tvari

2. Me

The tause clisive wcalculato theexpect(ranginprevioThese 44 parparticiof 34.Octobegave wwas apUniver

It mfeet rathe twparticiseparaMuntecal prothe infto peoaim ofof the of theconsist

Themore ttraumhavinglimb dals Lookilome

Thegraph DSC-P1 cleat to the head of the rst metatarsal, andnce from the distal end of the shoe to the baseeat);mine which of the longitudinal variables (dis-s the most important in the adjustment;

with a resocapacity odistance ofwas restingthat the dire partir de son extrmit distale.ervs.

uct regression models enabling adjustment of theof the cleat for each cyclist by using these varia-

null hypothesis of this study is that the positionleat could be the same for all cyclists, as the

studied do not have any inuence.

ds

population of this study consists of cyclists who road bike pedals and practice cycling in an inten-ore than 5000 km per year). The sample size waswith the software nQuery Advisor 4.0, accordingber of variables to relate (between 2 and 5), thealues of the coefcient of multiple correlationtween 0.14 and 0.68 in a pilot study carried out, a value for of 5%, and a 1- power of 80%.

gave a size of 88 feet. The sample consisted ofants (88 lower limbs: 44 right and 44 left). Sevens were women and 37 were men, with a mean age1.1 years old. This study was carried out duringovember and December 2008. Each participantn consent to take part in the study, and the studyed by the Experimental Ethics Committee of theof Seville.be pointed out that the authors refer always to

than persons, as the anthropometric variables ofet (right and left) may be different in the same, and in clinical practice the need to perform axamination to each foot is frequent. As Menz andxplained [17], the main conceptual and statisti-s generated by this type of approach arises whences derived from the studies are made in relation

having used feet as the unit of analysis. As the study is to analyze and relate the characteristicsr limb and the cleat, the authors used feet as unitple, and not the participants. Thus, the samplef 88 feet.lusion criteria were the following: cyclists aged20-years-old [1825], not having suffered severes or surgical operations on the lower limb, not

fered injuries caused by overloading the lower (at least) the previous year, using automatic ped-and with a sporting intensity of a minimum 5000

per year.iables were recorded using two tests: a photo-a radiograph. For the rst one, a Cyber-shotigital camera (Sony, San Diego, U.S.A.) was used,

lution of 5.1 mega pixels and an optical zoom

f 3x, placed on a tripod at a ground-to-camera 1 meter, completely vertical to the shoe, which

on the ground and centered on the screen suchstal and proximal ends of the shoe exactly tted

Antero-posterior position of the cleat for road cycling e57

the image frame. The dorsoplantar radiographs were madeusing a Sedecal SPS HF-4.0 X-ray equipment. The X-ray tubehad an inclination of 15 degrees to the vertical [26], anda tube-to-plate distance of 1 meter, according to the cri-teria of the Measurements and Terminology Committee ofthe Americ(AOFAS). Rditions, as [29]. The r10 mAs. Bestudy (theelement aof the shoobtained wimages onSeiko Epsotal image. using the soCalifornia)of the radi[3035].

The varwere age distance r(centimetethe forefooindex, plustem; 1 Paricleat and between t(%).

The angthe radioglongitudinaminor tars(Fig. 1) wasfrom the cleat. Howon the phothe distal ethe total le

Data wfor Windowcal puricaThe Kolmothe data fotest showeuse of parsamples waing on thesample. Lausing the cable in onmodel, anvariables. P < 0.05.

3. Resul

The valuesters, of all

Figure 1 Cleat-rst metatarsal distance.

the qualitative variable metatarsal index [36,37],were 26 cases of plus index, 60 of minus index, and

plus-minus index. The shoe size presented minimumaximum values of 39 and 46 respectively (measured

Figure 2 Tip-cleat distance.an Orthopaedic Foot and Ankle Society [27,28]adiographs were taken under weight-bearing con-this is the constant state of the foot in this sportadiological parameters employed were 65 Kv andcause of the radiotransparency of the piece under

cleat), it was decided to place a rigid metalt its base to act as a reference in the imagee when xed on the pedal. The radiograph thusas digitalized, using a scanner able to explore

negative lms (EPSON EXPRESSION 1680 Pro,n Corporation, Nagano, Japan) to create a digi-Measurements were made on the digital image,ftware AutoCAD 2006 (Autodesk Inc, San Rafael,. The protocol of digitalization and measurementographs has previously been used in other studies

iables studied (and their units of measurement)(years old), gender (male or female), annualidden (kilometers), weight (kilograms), heightrs), body mass index (BMI), angle of adduction oft (degrees), metatarsal index (plus index, minus-minus index), [36,37] shoe size (Paris Point Sys-s point = 6.67 millimeters), distance between thethe rst metatarsal (centimeters), and distancehe tip of the shoe and the base of the cleat

le of adduction of the forefoot was measured onraphs. It was formed by the intersection of thel axis of the second metatarsal with that of theus [3841]. The cleat/rst metatarsal distance

also measured on the radiograph, as the distancerst metatarsophalangeal joint to the base of theever, the tip/cleat distance (Fig. 2) was measuredtograph, as the ratio between the distance fromnd of the shoe (tip) to the base of the cleat, andngth of the shoe.ere analyzed by using the software SPSS 15.0s (SPSS Science, Chicago, Illinois). A statisti-tion was performed to detect atypical values.gorov-Smirnov test was used to check whetherllowed a normal distribution; the results of thisd a normal grouping of the data, validating theametric tests. A Student t-test for independents performed on the dependent variables depend-

side (right-left) to test the homogeneity of thestly, linear regression models were constructedleat/rst metatarsal distance as dependent vari-e model, and the tip/cleat distance in anotherd shoe size and metatarsal index as predictorThe value of P was considered signicant when

ts

of age, weight, height, BMI, and annual kilome- participants are shown in Table 1.

Forthere two ofand m

e58 J. Ramos Ortega et al.

Table 1 Age, weight, height, BMI, and annual kilometers, of all participants.

N Minimum Maximum Mean SD

Age (years) 88 19.00 62.00 34.41 11.09BMI 88 18.62 26.99 23.20 1.92Height 88 157 184 172 008Weight 88 52.00 84.00 68.79 7.92Annual km (km) 88 5000 30.000 12470.45 6243.58

Table 2 Mean, typical deviation, and condence interval to 95% for the quantitative variables.

Condence interval to 95%Variable Media DT Lower limit Upper limitAdduction of the forefoot (degrees) 13.3 0.4 12.4 14.2Cleat/rst metatarsal distance (cm) 3.6 0.8 3.4 3.7Tip/cleat distance (%) 0.43 0.42 0.43

as Paris points). Regarding the remaining variables, mean,standard deviation, and lower and upper limits for a con-dence interval of 95% are detailed in Table 2.

The results of the Student t-test for independent groupson the depleft) did nofor the varnor for the

The lineffects of able, so thby taking tvariable, adependent

3.1. Clea

R and R2 vatively (P = 0yielded the

of the cleat: rst metatarsal distance = 22.624 + (1.379shoe size).

ip/

2 va(P = 0d thf the

scu

ositiopmence and gh ne, t

Table 3

Model

Constant Shoe size

Elements ifor the mo

Table 4

Model

Constant Shoe size

Elements ifor the moendent...