title: Factor structure of trunk performance data for healthy subjects.
abstract: OBJECTIVE
  To examine the factor structure of various measurements of trunk muscle performance for healthy subjects.
  
  
  METHODS
  A total of 22 performance scores were collected and their univariate and multi-variate relationships were examined.
  
  
  BACKGROUND
  Extensive literature exists on the measurement of trunk performance data and the relationships between measurements but what needs to be collected to realize a true performance score remains unclear.
  
  
  METHODS
  Trunk muscle performance scores of 150 subjects (71 males and 79 females) were obtained on an Isostation B-200 Dynamometer. Twenty-two parameters measuring range of motion, isometric strength, velocity, and endurance on all three planes of motion were collected. The factor structures were constructed using Principal Components Analysis.
  
  
  RESULTS
  Clear-cut factor patterns (explained 96.3% of the total variance) suggests that the five-factor structure might be valid and appropriate for this population. The major loading on each factor indicated that: Factor 1 could be labeled as a static strength measure; Factor 2 as velocity; Factor 3 as flexibility; and Factors 4 and 5 as fatigue-resistance.
  
  
  CONCLUSIONS
  No single mode of measurement can provide a good representation of a total trunk muscle performance. RelevanceFor the realization of trunk muscle performance, clinics have to measure all modes of isometric strength, velocity, range of motion, and endurance. Care must be taken in eliminating any parameter.
authors.affiliation: Department of Industrial Management, National Taiwan University of Technology and Science, No. 43 Kee-Lung Road, Sec 4, Taipei, Taiwan, ROC. yhlee@im.ntust.edu.tw
authors.forename: Y
authors.initials: Y
authors.lastname: Lee
authors.forename: C
authors.initials: C
authors.lastname: Kuo
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D009068:Movement; D018482:Muscle, Skeletal / Q000502:physiology*; D010807:Physical Endurance; D012016:Reference Values