title: Isometric muscle strength in youth assessed by hand-held dynamometry: a feasibility, reliability, and validity study.
abstract: OBJECTIVE
  To determine, with respect to measurement of maximal isometric torque (MIT) using a specific hand-held dynamometer (HHD) protocol, (1) protocol feasibility over a wide age range, (2) intra- and interrater reliability, (3) standard error of measurement, and (4) concurrent validity.
  
  
  METHODS
  The MIT of selected upper and lower limb muscle groups was assessed (n = 74; age = 4-17.5 years) using a standardized, HHD protocol. Testing was repeated in 20 adolescents (n = 10 for each muscle group), who were also assessed with a Cybex dynamometer.
  
  
  RESULTS
  The protocol was feasible for all participants. Mean intra- and interrater reliability [intraclass correlation coefficient (ICC)] varied from 0.75 to 0.98, except for ankle dorsiflexor interrater reliability (mean ICC = 0.67). The standard error of measurement varied from 0.5 to 4.9 Nm and was highest for hip extensors. Mean concurrent validity (ICC) varied from 0.78 to 0.93, except for ankle plantar flexors (mean ICC = 0.48).
  
  
  CONCLUSIONS
  Our HHD protocol was feasible over a wide age range and most MIT values were valid and reliable.
authors.affiliation: National Defense of Canada, CFHS HQ-D Med Pol, Ottawa, Canada. ljhebert@videotron.ca
authors.forename: Luc J
authors.initials: LJ
authors.lastname: Hébert
authors.forename: Désirée B
authors.initials: DB
authors.lastname: Maltais
authors.forename: Céline
authors.initials: C
authors.lastname: Lepage
authors.forename: Joanne
authors.initials: J
authors.lastname: Saulnier
authors.forename: Mélanie
authors.initials: M
authors.lastname: Crête
authors.forename: Marc
authors.initials: M
authors.lastname: Perron
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000704:Analysis of Variance; D002648:Child; D002675:Child, Preschool; D002985:Clinical Protocols; D016001:Confidence Intervals; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000502:physiology*; D010372:Pediatrics / Q000295:instrumentation / Q000379:methods; D026741:Physical Therapy Modalities / Q000295:instrumentation*; D015203:Reproducibility of Results; D013223:Statistics as Topic; D013334:Students; D019415:Torque