title: Postural stability in young healthy subjects - Impact of reduced base of support, visual deprivation, dual tasking.
abstract: OBJECTIVE
  To provide normative postural stability data in young subjects.
  
  
  METHODS
  Ninety-six healthy participants (58W, 28±6y) stood on a force plate during 60s. We measured effects of support width (feet apart, FA; feet together, FT), vision (eyes open, EO; closed, EC), and cognitive load (single task, ST; dual tasking, DT) on anteroposterior (AP) and medio-lateral (ML) ranges, area and planar velocity of center of pressure (COP) trajectory.
  
  
  RESULTS
  All variables increased with FT (AP range, +15%; ML, +185%; area, +242%; velocity, +50%, p<0.0002 for all, MANOVA). Visual deprivation increased COP ranges with added constraints (FT or DT, p=0.002) and increased velocity in all conditions (FA/ST, +16%; DT, +18%; FT/ST, +29%; DT, +23%, p<0.0002 for all). Dual tasking reduced COP displacements with FT (AP range, EO, -15%; EC, -11%; ML range, EO, -19%; EC, -13%; area, EO, -40%; EC, -28%, p<0.0002 for all) and increased velocity in most conditions (FA/EO, +15%; FA/EC, +16%; FT/EO, +7%, p<0.0002 for all).
  
  
  CONCLUSIONS
  In young healthy adults, base of support reduction increases COP displacements. Vision particularly affects postural stability with feet together or dual tasking. Dual tasking increases velocity but decreases COP displacements in challenging postural tasks, potentially by enhanced lower limb stiffness.
authors.affiliation: Laboratoire Analyse et Restauration du Mouvement (ARM), Bioingénierie, Tissus et Neuroplasticité (BIOTN), EA 7377, Hôpitaux Universitaires Henri Mondor, Assistance Publique des Hôpitaux de Paris (AP-HP), Université Paris-Est Créteil (UPEC), France; Altonaer Kinderkrankenhaus gGmbH, Ganglabor, Bleickenallee 38, Hamburg 22763, Germany. Electronic address: inkemarie.albertsen@gmx.de.
authors.forename: Inke Marie
authors.initials: IM
authors.lastname: Albertsen
authors.affiliation: Laboratoire Analyse et Restauration du Mouvement (ARM), Bioingénierie, Tissus et Neuroplasticité (BIOTN), EA 7377, Hôpitaux Universitaires Henri Mondor, Assistance Publique des Hôpitaux de Paris (AP-HP), Université Paris-Est Créteil (UPEC), France.
authors.forename: Mouna
authors.initials: M
authors.lastname: Ghédira
authors.affiliation: Laboratoire Analyse et Restauration du Mouvement (ARM), Bioingénierie, Tissus et Neuroplasticité (BIOTN), EA 7377, Hôpitaux Universitaires Henri Mondor, Assistance Publique des Hôpitaux de Paris (AP-HP), Université Paris-Est Créteil (UPEC), France.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Gracies
authors.affiliation: Laboratoire Analyse et Restauration du Mouvement (ARM), Bioingénierie, Tissus et Neuroplasticité (BIOTN), EA 7377, Hôpitaux Universitaires Henri Mondor, Assistance Publique des Hôpitaux de Paris (AP-HP), Université Paris-Est Créteil (UPEC), France.
authors.forename: Émilie
authors.initials: É
authors.lastname: Hutin
mesh_terms: D000328:Adult; D005260:Female; D005528:Foot / Q000502:physiology; D064368:Healthy Volunteers; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology; D004856:Postural Balance; D011187:Posture; D011597:Psychomotor Performance; D014796:Visual Perception
keywords: Balance; COP trajectories; Center of pressure; Cognitive load; Force plate; Normative data