title: Relationship between ambulatory physical activity assessed by activity trackers and physical frailty among nursing home residents.
abstract: The aim of this study was to assess the relationship between the level of ambulatory physical activity, measured by physical activity tracker, and the clinical components of physical frailty, among nursing home residents.
  
  
  
  We proceeded in 3 steps: (1) Validation of the physical activity tracker (i.e. the Pebble): 24 volunteer adults walked on a treadmill. The number of steps recorded by the Pebble worn by the subjects was compared with the number of steps counted by the investigators, by means of the Intra-class correlation coefficients (ICC). (2) Measurement of ambulatory physical activity, using the Pebble trackers, over a 7-day period. (3) Relationship between the results obtained with the Pebble trackers (step 2) and subjects' clinical characteristics, linked to physical frailty.
  
  
  
  ICC data, showed that the reliability of the Pebble was better when it was worn at the foot level (ICC ranged from 0.60 to 0.93 depending on the tested speed). Gait speed is also an important determinant of the reliability, which is better for low gait speed. On average, the 27 nursing home residents included in the second step of this study walked 1678.4±1621 (median=1300) steps per day. Most physical components of frailty measured in this study were significantly different between subjects who walked less than 1300 steps per day and those who were more active.
  
  
  
  This study showed that nursing home residents have a poor ambulatory physical activity, assessed using a physical activity tracker, which is associated with poorer physical performances and higher disability.
authors.affiliation: Department of Public health, Epidemiology and health Economics, University of Liège, Liège, Belgium; Support Unit in Epidemiology and Biostatistics, University of Liège, Liège, Belgium. Electronic address: fanny.buckinx@ulg.ac.be.
authors.forename: F
authors.initials: F
authors.lastname: Buckinx
authors.affiliation: Sport Sciences Department, University of Liège, Liège, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Mouton
authors.affiliation: Department of Public health, Epidemiology and health Economics, University of Liège, Liège, Belgium; Support Unit in Epidemiology and Biostatistics, University of Liège, Liège, Belgium.
authors.forename: J Y
authors.initials: JY
authors.lastname: Reginster
authors.affiliation: Sport Sciences Department, University of Liège, Liège, Belgium.
authors.forename: J L
authors.initials: JL
authors.lastname: Croisier
authors.affiliation: Department of Public health, Epidemiology and health Economics, University of Liège, Liège, Belgium; Support Unit in Epidemiology and Biostatistics, University of Liège, Liège, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Dardenne
authors.affiliation: Department of Public health, Epidemiology and health Economics, University of Liège, Liège, Belgium; Support Unit in Epidemiology and Biostatistics, University of Liège, Liège, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Beaudart
authors.affiliation: Sport Sciences Department, University of Liège, Liège, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Nelis
authors.affiliation: Sport Sciences Department, University of Liège, Liège, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Lambert
authors.affiliation: Department of Neurosurgery, Stanford University Medical Center, 300 Pasteur Drive, Stanford, CA 94305, USA; Byers Center for Biodesign, Stanford University, 318 Campus Drive E100, Stanford, CA 94305, USA.
authors.forename: G
authors.initials: G
authors.lastname: Appelboom
authors.affiliation: Department of Public health, Epidemiology and health Economics, University of Liège, Liège, Belgium; Support Unit in Epidemiology and Biostatistics, University of Liège, Liège, Belgium; Sport Sciences Department, University of Liège, Liège, Belgium.
authors.forename: O
authors.initials: O
authors.lastname: Bruyère
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D000072936:Fitness Trackers; D016330:Frail Elderly; D006707:Homes for the Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D009735:Nursing Homes; D015203:Reproducibility of Results; D016138:Walking
keywords: Activity tracker; Ambulatory physical activity; Elderly; Nursing home; Physical frailty; Steps