title: Convergent evidence for construct validity of a 7-point likert scale of lower limb muscle soreness.
abstract: OBJECTIVE
  The aim of this study was to examine the construct validity of the 7-point Likert scale of muscle soreness, assessing its relationship with Visual Analogue Scale (VAS). An additional aim was to examine its sensitivity as measure of symptom of eccentric-contraction muscle damage.
  
  
  METHODS
  Correlational study.
  
  
  METHODS
  Self-administered questionnaires collected in field setting.
  
  
  METHODS
  Twenty-six soccer players.
  
  
  METHODS
  4-week preseason training camp, which included high-intensity plyometric training sessions.
  
  
  METHODS
  Players self-reported the perceived muscle soreness of the lower limbs using the VAS (criterion measure) and the 7-point Likert scale of muscle soreness.
  
  
  RESULTS
  Significant individual correlations were found between the 2 muscle soreness scales (mean r=0.80+/-0.07; range, 0.65 to 0.94). The correlation using the pooled data was 0.81. No significant muscle soreness scale x time interaction was found for standardized measures of muscle soreness (P=0.98). The main factor for time (24, 48, 72, and 96 hours after the first plyometric training session) was significant (P=0.0001). Effect sizes for the changes in the Likert and VAS absolute scores during the first 96 hours were similar (partial eta=0.13).
  
  
  CONCLUSIONS
  The results of this study provide further convergent evidence for the construct validity of the 7-point Likert scale of muscle soreness. The 2 scales showed similar sensitivity to muscle soreness caused by eccentric contractions during the first 96 hours after plyometric exercises.
authors.affiliation: Neuromuscular Research Laboratory, Schulthess Clinic, Zurich, Switzerland. franco.impellizzeri@kws.ch
authors.forename: Franco M
authors.initials: FM
authors.lastname: Impellizzeri
authors.forename: Nicola A
authors.initials: NA
authors.lastname: Maffiuletti
mesh_terms: D000328:Adult; D019317:Evidence-Based Medicine; D006801:Humans; D007869:Leg Injuries / Q000473:pathology*; D018482:Muscle, Skeletal / Q000293:injuries* / Q000473:pathology; D010147:Pain Measurement; D012680:Sensitivity and Specificity; D012916:Soccer; D013223:Statistics as Topic; D011795:Surveys and Questionnaires