title: How is walking speed related to muscle strength? A study of healthy persons and persons with late effects of polio.
abstract: OBJECTIVE
  To evaluate the relationship between walking speed and muscle strength in the lower extremities in healthy persons and in persons with late effects of polio and to compare the models for these relationships.
  
  
  METHODS
  Retrospective analysis.
  
  
  METHODS
  University hospital department.
  
  
  METHODS
  An urban sample of 144 healthy men and women (age range, 40-79 y) and 234 (146 women, 88 men) subjects with late polio.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Muscle strength in the lower extremities was measured and combined into an index. Walking speed for spontaneous and maximal walking was measured. A nonlinear regression model was developed.
  
  
  RESULTS
  Evidence was provided for the nonlinear relationship between walking speed and strength. A specific strength threshold could not be identified. The asymptote of this curve for maximal walking was 2.57 m/s in the healthy group and 2.02 m/s in the subjects with late effects of polio. A high body mass index (>25 kg/m2) lowered the asymptote.
  
  
  CONCLUSIONS
  It is important to prevent strength decrease that approaches the critical level where a further reduction affects walking speed more evidently. The difference in the relationship between muscle strength and walking speed for the 2 groups studied may partly depend on biomechanic imbalance between muscle groups.
authors.affiliation: Institute of Neurosciences-Rehabilitation Medicine, Sahlgrenska Academy, University of Göteborg, Sweden.
authors.forename: Carin
authors.initials: C
authors.lastname: Willén
authors.forename: Katarina Stibrant
authors.initials: KS
authors.lastname: Sunnerhagen
authors.forename: Claes
authors.initials: C
authors.lastname: Ekman
authors.forename: Gunnar
authors.initials: G
authors.lastname: Grimby
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000503:physiopathology*; D011051:Poliomyelitis / Q000503:physiopathology*; D012044:Regression Analysis; D012189:Retrospective Studies; D012656:Self-Help Devices; D012737:Sex Factors; D016138:Walking / Q000502:physiology*