title: Test-retest reliabilty of isokinetic hip adductor and flexor muscle strength.
abstract: OBJECTIVE
  To determine the test-retest reliability of eccentric hip flexor and adductor peak torque and endurance using a Cybex Norm isokinetic dynamometer and to evaluate muscle soreness after exercise as a result of the testing procedure.
  
  
  METHODS
  Prospective test-retest reliability study.
  
  
  METHODS
  A total of 19 male volunteers (21-43 years old).
  
  
  METHODS
  Tests included hip flexor and adductor peak torque strength measured at 60 degrees/s (concentric and eccentric) and endurance measurements (total work done over 20 continuous concentric/eccentric contractions at 150 degrees/s). Subjects were tested on three occasions at 1-week intervals.
  
  
  METHODS
  Repeated measures analysis of variance was performed for all dependent variables including the subject's dominant and nondominant side among the three test sessions. Intraclass correlation coefficients (ICCs) were calculated to compare the data between sessions. In addition, simple linear regression analysis was completed to determine the relationship between session measurements for all measures with ICC > 0.75.
  
  
  RESULTS
  The main findings of this study are that eccentric peak hip adductor torque was reliably measured on a Cybex Norm isokinetic dynamometer using a continuous eccentric/ concentric cycle protocol at a speed of 60 degrees/s (ICC > 0.84). Peak concentric adductor torque and peak eccentric and concentric hip flexor torque were less reliable using the same protocol (ICC < 0.67). Endurance measurements, using total work done over 20 repetitions, were not reliable for hip flexor and adductor muscle groups using a continuous eccentric/concentric cycle protocol at a speed of 150 degrees/s (ICC < 0.55). Posttest muscle soreness was found to be of significant concern with such a protocol.
  
  
  CONCLUSIONS
  The results from this test-retest reliability study confirm the reliability of eccentric peak hip adductor torque measurements for use clinically and in future research. In addition, the need to assess posttest muscle soreness after isokinetic muscle testing is confirmed.
authors.affiliation: Department of Community Health Sciences, Faculty of Medicine, University of Calgary, Alberta, Canada.
authors.forename: C A
authors.initials: CA
authors.lastname: Emery
authors.forename: M E
authors.initials: ME
authors.lastname: Maitland
authors.forename: W H
authors.initials: WH
authors.lastname: Meeuwisse
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016001:Confidence Intervals; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology; D015203:Reproducibility of Results