title: Effects of flooring on required coefficient of friction: Elderly adult vs. middle-aged adult barefoot gait.
abstract: The aim of this study was to investigate the effect of flooring on barefoot gait according to age and gender. Two groups of healthy subjects were analyzed: the elderly adult group (EA; 10 healthy subjects) and the middle-aged group (MA; 10 healthy subjects). Each participant was asked to walk at his or her preferred speed over two force plates on the following surfaces: 1) homogeneous vinyl (HOV), 2) carpet, 3) heterogeneous vinyl (HTV) and 4) mixed (in which the first half of the pathway was covered by HOV and the second by HTV). Two force plates (Kistler 9286BA) embedded in the data collection room floor measured the ground reaction forces and friction. The required coefficient of friction (RCOF) was analyzed. For the statistical analysis, a linear mixed-effects model for repeated measures was performed. During barefoot gait, there were differences in the RCOF among the flooring types during the heel contact and toe-off phases. Due to better plantar proprioception during barefoot gait, the EA and MA subjects were able to distinguish differences among the flooring types. Moreover, when the EA were compared with the MA subjects, differences could be observed in the RCOF during the toe-off phase, and gender differences in the RCOF could also be observed during the heel contact phase in barefoot gait.
authors.affiliation: Laboratory of Instrumentation for Biomechanics, College of Physical Education, University of Campinas, Campinas, Brazil; CAPES Foundation, Ministry of Education of Brazil, DF CEP: 70.040-020, Brazil; "Luigi Divieti" Posture and Movement Analysis Laboratory, Department of Electronics, Information and Bioengineering, Politecnico di Milano, Piazza leonardo da Vinci 32, 20133 Milano, Italy. Electronic address: anafrkleiner@gmail.com.
authors.forename: Ana Francisca
authors.initials: AF
authors.lastname: Rozin Kleiner
authors.affiliation: "Luigi Divieti" Posture and Movement Analysis Laboratory, Department of Electronics, Information and Bioengineering, Politecnico di Milano, Piazza leonardo da Vinci 32, 20133 Milano, Italy; "Motion Analysis Lab", IRCCS San Raffaele Pisana, Via della Pisana, 235, Rome, Italy. Electronic address: manuela.galli@polimi.it.
authors.forename: Manuela
authors.initials: M
authors.lastname: Galli
authors.affiliation: Laboratory of Instrumentation for Biomechanics, College of Physical Education, University of Campinas, Campinas, Brazil; University of Brasilia, QNN14, Área Especial, Ceilândia Sul, Distrito Federal CEP: 72.220-710, Brazil. Electronic address: alinecarmo@unb.br.
authors.forename: Aline
authors.initials: A
authors.lastname: Araujo do Carmo
authors.affiliation: Laboratory of Instrumentation for Biomechanics, College of Physical Education, University of Campinas, Campinas, Brazil. Electronic address: ricardo@fef.unicamp.br.
authors.forename: Ricardo M L
authors.initials: RM
authors.lastname: Barros
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control; D000367:Age Factors; D000368:Aged; D005260:Female; D005430:Floors and Floorcoverings / Q000379:methods / Q000592:standards; D005528:Foot / Q000502:physiology; D017276:Friction / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged
keywords: Barefoot; Elderly; Gait