title: Isokinetic trunk and lifting strength measurements: variability as an indicator of effort.
abstract: This study examines the hypothesis that force/distance curve variability distinguishes submaximal from maximal efforts in isokinetic trunk and lifting strength tests. Thirty normal subjects were tested on the Cybex Trunk Extension/Flexion (TEF) and Liftask (LT) machines during maximal (100%) and submaximal (50%) efforts. Considering each test separately, visual assessments of curve variability were indeterminate of degree of effort in 28% of TEF and 34% of LT tests. Measurement models of curve variability were more clearly discriminating. When a given subject's test curves were considered together, scaled visual assessments identified the degree of effort in 91% of TEF and 86% of LT results. The measurement models were accurate 90-92% of TEF and 79-92% of LT results. Clinical judgment is required in evaluating effort during tests of isokinetic trunk and lifting strength.
authors: Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington 05401.
authors: R G
authors: RG
authors: Hazard
authors: S
authors: S
authors: Reid
authors: J
authors: J
authors: Fenwick
authors: V
authors: V
authors: Reeves
mesh_terms: D000328:Adult; D005260:Female; D006339:Heart Rate; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D009132:Muscles / Q000502:physiology; D005082:Physical Exertion