Concentric and eccentric torque comparisons for knee extension and flexion in young adult males and females using the Kinetic Communicator

The purposes of this investigation were to establish average leg torque values as a proportion of body weight for both concentric and eccentric contractions for leg extension and leg flexion, to determine leg flexion/extension ratios for both concentric and eccen tric contractions, and to compare those values in males and females from ages 15 to 34 years.

The Kinetic Communicator (Kin-Com, Chattecx Corp., Chattanooga, TN), a relatively new computerized strength testing device, was used so that both concen tric and eccentric torques could be measured. Pilot study results indicated that Kin-Com results were reli able, r > 0.88. Average torque, across the full range of motion, and peak torque expressed in newton meters were divided by body weight in kilograms to produce torque values adjusted by body weight. No differences across age or sex were observed for floxion/extension ratios, but the males' weight-adjusted torque values were significantly (P < 0.01) greater than the females'. Younger (ages 15 to 24 years) male and female sub jects produced significantly (P < 0.01) greater torque for concentric contractions than older subjects (25 to 34 years). In rehabilitation programs using the Kin-Com, the weight-adjusted torque values and flexion/exten sion ratios will be useful in determining patients' strength recovery from knee or leg injury and/or sur gery.