title: A comparison of muscle stiffness and musculoarticular stiffness of the knee joint in young athletic males and females.
abstract: The objective of this study was to investigate the gender-specific differences in peak torque (PT), muscle stiffness (MS) and musculoarticular stiffness (MAS) of the knee joints in a young active population. Twenty-two male and twenty-two female recreational athletes participated. PT of the knee joint extensor musculature was assessed on an isokinetic dynamometer, MS of the vastus lateralis (VL) muscle was measured in both relaxed and contracted conditions, and knee joint MAS was quantified using the free oscillation technique. Significant gender differences were observed for all dependent variables. Females demonstrated less normalized PT (mean difference (MD)=0.4Nm/kg, p=0.005, η(2)=0.17), relaxed MS (MD=94.2N/m, p<.001, η(2)=0.53), contracted MS (MD=162.7N/m, p<.001, η(2)=0.53) and MAS (MD=422.1N/m, p<.001, η(2)=0.23) than males. MAS increased linearly with the external load in both genders with males demonstrating a significantly higher slope (p=0.019) than females. The observed differences outlined above may contribute to the higher knee joint injury incidence and prevalence in females when compared to males.
authors.affiliation: School of Public Health, Physiotherapy and Population Science, University College Dublin, Health Sciences Centre, Belfield, Dublin 4, Ireland; The No. 2 Clinical Medicine School, Nanjing University of Chinese Medicine, Nanjing, Jiang Su Province, China. Electronic address: dan.wang@ucdconnect.ie.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: School of Public Health, Physiotherapy and Population Science, University College Dublin, Health Sciences Centre, Belfield, Dublin 4, Ireland; Institute for Sport and Health, University College Dublin, Dublin, Ireland.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: De Vito
authors.affiliation: Department of Sport, Health & Exercise Science, Faculty of Science & Engineering, University of Hull, England, United Kingdom.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Ditroilo
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire LE11 3TU, United Kingdom.
authors.forename: Daniel T P
authors.initials: DT
authors.lastname: Fong
authors.affiliation: School of Public Health, Physiotherapy and Population Science, University College Dublin, Health Sciences Centre, Belfield, Dublin 4, Ireland; Institute for Sport and Health, University College Dublin, Dublin, Ireland.
authors.forename: Eamonn
authors.initials: E
authors.lastname: Delahunt
mesh_terms: D000328:Adult; D056352:Athletes; D002358:Cartilage, Articular / Q000473:pathology / Q000502:physiology*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology / Q000502:physiology*; D052097:Quadriceps Muscle / Q000473:pathology / Q000502:physiology; D012727:Sex Characteristics; D013177:Sports / Q000502:physiology*; D055815:Young Adult
keywords: Athletic injuries; Knee joint; Neuromuscular monitoring; Quadriceps muscle