THE RELATIONSHIPS AMONG KNEE EXTENSOR TORQUES PRODUCED DURING MAXIMAL VOLUNTARY CONTRACTIONS UNDER VARIOUS TEST CONDITIONS

Background and Purpose. The purpose of this study was to describe the relationships among measurements of torque produced during selected maximal voluntary contractions of the quadriceps femoris muscles. Subjects. Twenty nondisabled women, ranging in age from 21 to 33 years (XBAR=25, SD=3.5), volunteered to participate in the study. Methods. The subjects were tested on a dynamometer. Subjects performed isometric contractions at 40 and 60 degrees of knee flexion and concentric and eccentric isokinetic contractions at velocities of 30-degrees, 90-degrees, 120-degrees, and 180-degrees/s. Isometric knee extensor torques, concentric knee extensor peak torques, and eccentric knee extensor peak torques were determined for each subject. Coefficients of determination (r2) and linear regression equations were calculated to determine the strength and nature of the relationships among the measurements. Results. The coefficients of determination ranged from .60 to .94. Conclusion and Discussion. The torque measurements were moderately to highly correlated, suggesting that the measurements obtained during different maximal voluntary contractions may be assessing similar components of performance. [Kues JM, Rothstein JM, Lamb RL. The relationships among knee extensor torques produced during maximal voluntary contractions under various test conditions. Phys Ther. 1994;74:674-683.]