title: Actual and perceived activity levels in polio survivors and older controls: a longitudinal study.
abstract: OBJECTIVE
  To examine factors associated with daily step activity, perceived activity, maximum walking speed, and walking speed reserve over time in polio survivors and older adults with no history of polio.
  
  
  METHODS
  Longitudinal study.
  
  
  METHODS
  A research clinic and the community.
  
  
  METHODS
  Polio survivors (n=96; 65 in postpolio syndrome [PPS] group, 31 in non-PPS group) and older adults (n=112) with no history of polio.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Daily step activity, perceived activity, maximum walking speed, and walking speed reserve.
  
  
  RESULTS
  Results showed decreases in perceived activity over time in the PPS group. However, there was no change in average daily walking activity. Overall, polio survivors walk less and have a smaller walking speed reserve than controls. Knee strength was positively associated with maximum walking speed and walking speed reserve in all groups. Weight and age were associated with daily step activity in controls but not polio survivors.
  
  
  CONCLUSIONS
  Daily walking activity did not change statistically over the 3-year study period, although perceived activity and the walking speed reserve decreased among polio survivors with PPS. On average, polio survivors appear to function with minimal functional reserve, as their preferred walking speed was close to their maximum speed.
authors.affiliation: Moss Rehabilitation Research Institute, Philadelphia, PA; Thomas Jefferson University, Philadelphia 19141, USA. mklein@einstein.edu
authors.forename: Mary G
authors.initials: MG
authors.lastname: Klein
authors.forename: Leonard E
authors.initials: LE
authors.lastname: Braitman
authors.forename: Roberta
authors.initials: R
authors.lastname: Costello
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Keenan
authors.forename: Alberto
authors.initials: A
authors.lastname: Esquenazi
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011051:Poliomyelitis / Q000503:physiopathology*; D016262:Postpoliomyelitis Syndrome / Q000503:physiopathology*; D012649:Self Concept; D017741:Survivors; D016138:Walking / Q000502:physiology*