title: Reliability of knee biomechanics during a vertical drop jump in elite female athletes.
abstract: The purpose of the study was to assess the within-session and between-session reliability of knee kinematics and kinetics in a vertical drop jump task among elite female handball and football athletes. Specifically, we aimed to quantify the within-session waveform consistency and between-session consistency of the subject ranking for a variety of knee kinematics and kinetics. Forty-one elite female handball and football (soccer) athletes were tested in two sessions. The reliability of three-dimensional knee biomechanical measurements was quantified by the intra-class correlation, Spearman's rank correlation, and typical error. All the selected discrete variables achieved excellent within-session reliability (ICC>0.87). The typical error of valgus angles, internal rotation angles, and internal rotation moment was constant throughout the whole stance phase. For between-session reliability, the selected discrete variables achieved good to excellent reliability (ICC>0.69), except peak internal rotation moment (ICC=0.40). All between-session rank correlation coefficients ranged from 0.56 to 0.90. Most of the discrete variables achieved good to excellent reliability in both within-session and between-session analysis. Moreover, moderate to strong between-session consistency of subject rankings was found, implying that the measurements assessed during the vertical drop jump demonstrate sufficient reliability to be used in both single-session and multiple-session studies.
authors.affiliation: Oslo Sports Trauma Research Center, Norwegian School of Sport Sciences, Oslo, Norway; Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: k.m.mok@nih.no.
authors.forename: Kam-Ming
authors.initials: KM
authors.lastname: Mok
authors.affiliation: Michigan State University, College of Human Medicine, East Lansing, Michigan, USA.
authors.forename: Erich
authors.initials: E
authors.lastname: Petushek
authors.affiliation: Oslo Sports Trauma Research Center, Norwegian School of Sport Sciences, Oslo, Norway. Electronic address: tron.krosshaug@nih.no.
authors.forename: Tron
authors.initials: T
authors.lastname: Krosshaug
mesh_terms: D056352:Athletes; D001696:Biomechanical Phenomena; D015444:Exercise; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D013177:Sports / Q000502:physiology*; D055815:Young Adult
keywords: 3D motion analysis; ACL injury; Knee kinematics and kinetics; Rank of individuals; Repeatability; Risk screening