title: Dynamic joint stiffness of the ankle during walking: gender-related differences.
abstract: OBJECTIVE
  To characterize and compare dynamic joint stiffness (DJS) of the ankle in the sagittal plane during natural cadence walking in both genders.
  
  
  METHODS
  Observation, cross-sectional and matched pairs.
  
  
  METHODS
  Twenty-one males (mean age=27+/-4.2 years) and 18 females (mean age=22.9+/-4.1 years).
  
  
  METHODS
  Laboratory at the University de Trás-os-Montes and Alto Douro. The DJS of the ankle was assessed while participants performed barefoot walking at a natural cadence, was measured using a force platform (1000 Hz), and synchronized with a high-speed camera (200 Hz).
  
  
  METHODS
  DJS of the ankle in males and females was calculated in two sub-phases (the second and the fourth sub-phases) of the stance phase. The Wilcoxon non-parametric matched-pairs test and the Mann-Whitney U non-parametric test were used to analyse difference of DJS of the ankle within and between the groups with p0.05 regarded as significant.
  
  
  RESULTS
  Male and female participants demonstrated significantly (p<0.005) less DJS during the second sub-phase. DJS was not significantly (p>0.063) different between females (0.0511 N m/kg/ degrees ) and males (0.0596 N m/kg/ degrees ) during the second sub-phase. DJS was significantly (p<0.001) higher in males (0.0844 N m/kg/ degrees ) than females (0.0691 N m/kg/ degrees ) during the fourth sub-phase.
  
  
  CONCLUSIONS
  Gender-specific DJS characteristics demonstrated by females in this study may be used in preventative training programs designed to promote a greater ability to use contractile components to produce mechanical energy through the ankle.
authors.affiliation: Human Movement Biomechanics Laboratory, Department of Sport-CETAV, University of Tras-os-Montes and Alto Douro, Vila Real, Portugal. rgabriel@utad.pt
authors.forename: Ronaldo C
authors.initials: RC
authors.lastname: Gabriel
authors.forename: João
authors.initials: J
authors.lastname: Abrantes
authors.forename: Kevin
authors.initials: K
authors.lastname: Granata
authors.forename: José
authors.initials: J
authors.lastname: Bulas-Cruz
authors.forename: Pedro
authors.initials: P
authors.lastname: Melo-Pinto
authors.forename: Vitor
authors.initials: V
authors.lastname: Filipe
mesh_terms: D000293:Adolescent; D000328:Adult; D000843:Ankle Joint / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology; D008124:Locomotion; D008297:Male; D010146:Pain; D016138:Walking / Q000502:physiology*; D055815:Young Adult