[Sincerity of effort: isokinetic evaluation of knee extension].

The aim of this study was to find a reliable method to evaluate the sincerity of the muscular maximal effort performed in a dynamometric isokinetic test of knee flexion-extension. The coefficient of variation of the peak torque (CV) and 3 new indices were analysed: (1) the average coefficient of variation calculated on the complete peak torque curve (CVM); (2) the slope of the regression line in an endurance test (PRR); (3) the correlation coefficient of the peak torques in the same endurance test (CCR). Twenty healthy subjects underwent assessment in two different trials, maximal (MX) and 50% submaximal (SMX), with 20 minutes of rest between trials.