668<strong>Muscle</strong> <strong>strength</strong> <strong>and</strong> movement pattern <strong>differences</strong>Most importantly, our results clearly demonstratethat muscle <strong>strength</strong> <strong>and</strong> anthropometric factors do NOTcontribute significantly to l<strong>and</strong><strong>in</strong>g movement patterns asmeasured by the LESS. Multivariate analysis showed verylittle contribution from anthropometric <strong>and</strong> <strong>strength</strong> valuesto overall movement patterns (R 2 = 0.016 for <strong>male</strong>s,0.014 for fe<strong>male</strong>s). This is a novel f<strong>in</strong>d<strong>in</strong>g. The primarytenants of many ACL <strong>in</strong>jury prevention programs averthat <strong>in</strong>creased lower extremity muscular will translate toimproved movement patterns dur<strong>in</strong>g athletic manoeuvres.In contrast, our f<strong>in</strong>d<strong>in</strong>gs suggest that simply chang<strong>in</strong>g anathlete’s alignment, BMI, or muscle <strong>strength</strong> may notultimately improve his or her movement patterns. Rather,l<strong>and</strong><strong>in</strong>g movements seem to be primarily determ<strong>in</strong>ed bycharacteristics other than <strong>strength</strong>, alignment, or bodymass. Future <strong>in</strong>vestigations should verify this lack ofcorrelation us<strong>in</strong>g traditional biomechanical methods. Ifconfirmed, the absence of a correlation <strong>in</strong> anthropometrics<strong>and</strong> muscle <strong>strength</strong> with an <strong>in</strong>dividual’s movement patternwould necessitate a paradigm shift <strong>in</strong> future <strong>in</strong>juryprevention <strong>in</strong>tervention design.Study limitationsWe caution that the use of a military population may limitthe generalizability of these results to all populations ofyoung athletes. Specifically, the overall athleticism, BMI,or fitness of the military academy population may besignificantly different than that of other populations. Additionally,although we have measured l<strong>and</strong><strong>in</strong>g movementpatterns <strong>in</strong> terms of “errors”—a common practice <strong>in</strong><strong>qualitative</strong> movement screen<strong>in</strong>g—we recognize that <strong>differences</strong><strong>in</strong> movement patterns cannot def<strong>in</strong>itively beclassified as errant unless prospectively l<strong>in</strong>ked to <strong>in</strong>juryrisk.ConclusionMale <strong>and</strong> fe<strong>male</strong> military cadets have <strong>differences</strong> <strong>in</strong> <strong>jump</strong>l<strong>and</strong><strong>in</strong>gtechnique as assessed through a <strong>qualitative</strong>movement screen. Fe<strong>male</strong>s demonstrate dist<strong>in</strong>ct l<strong>and</strong><strong>in</strong>gmovement patterns versus <strong>male</strong>s. L<strong>and</strong><strong>in</strong>g-error patternsmore common <strong>in</strong> <strong>male</strong>s <strong>and</strong> those more common <strong>in</strong> fe<strong>male</strong>sconta<strong>in</strong> features that have been previously postulatedto <strong>in</strong>crease ACL <strong>in</strong>jury risk. Most importantly, BMI,navicular drop, Q-angle, <strong>and</strong> muscular <strong>strength</strong> do notsignificantly predict movement patterns <strong>in</strong> either <strong>male</strong> orfe<strong>male</strong> cadets. 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American Journal of Sports Medic<strong>in</strong>e20, 208-211.Key po<strong>in</strong>ts• Important <strong>differences</strong> <strong>in</strong> <strong>male</strong> <strong>and</strong> fe<strong>male</strong> l<strong>and</strong><strong>in</strong>gtechnique can be captured us<strong>in</strong>g a <strong>qualitative</strong>movement screen: the L<strong>and</strong><strong>in</strong>g Error Scor<strong>in</strong>g System(LESS)• Fe<strong>male</strong> cadets were more likely to l<strong>and</strong> with shallowsagittal flexion, wide stance width, <strong>and</strong> more pronouncedknee flexion.• Male cadets were more likely to exhibit a heel-strikeor asymmetric foot-strike <strong>and</strong> to l<strong>and</strong> with toe out.• Lower extremity muscle <strong>strength</strong>, Q-angle, <strong>and</strong>navicular drop do not significantly predict l<strong>and</strong><strong>in</strong>gmovement pattern <strong>in</strong> <strong>male</strong> or fe<strong>male</strong> cadets.AUTHORS BIOGRAPHYAnthony I. BEUTLEREmploymentMajor, US Air Force,Chief, Injury PreventionResearch Lab, Uniformed ServicesUniversityDegreeMDResearch <strong>in</strong>terestsACL Injury, Injury Prevention, MusculoskeletalEducationE-mail: abeutler@usuhs.milSarah J. de la MOTTEEmploymentPost Doctoral Fellow, Injury PreventionResearch Lab, Uniformed Services UniversityDegreePhD, ATCResearch <strong>in</strong>terestsACL Injury, Ankle Injury, Injury PreventionE-mail: sarah.delamotte@usuhs.milStephen W. MARSHALLEmploymentAssociate Professor, Department of Epidemiology,School of Public HealthUniversity of North Carol<strong>in</strong>a, Chapel HillDegreePhDResearch <strong>in</strong>terestsInjury Prevention, Violence PreventionE-mail: smarshall@unc.eduDar<strong>in</strong> A. PADUAEmploymentAssociate Professor, Department of Exercise& Sport Science, University of NorthCarol<strong>in</strong>a, Chapel HillDegreePhD, ATCResearch <strong>in</strong>terestsACL Injury Prevention, NeuromuscularControlE-mail: dpadua@email.unc.eduBarry P. BODENEmploymentBoard Certified Orthopaedic SurgeonThe Orthopaedic Center, Rockville, MDDegreeMDResearch <strong>in</strong>terestsACL Injury, Head InjuryE-mail: bboden@starpower.net Anthony I. BeutlerUniformed Services University of the Health Sciences, Bethesda,MD, USA
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