THE RELATIONSHIPS AMONG KNEE EXTENSOR TORQUES PRODUCED DURING MAXIMALVOLUNTARY 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 ma ximal voluntary contractions of the quadriceps femoris muscles. Subjec ts. Twenty nondisabled women, ranging in age from 21 to 33 years (XBAR =25, SD=3.5), volunteered to participate in the study. Methods. The su bjects were tested on a dynamometer. Subjects performed isometric cont ractions at 40 and 60 degrees of knee flexion and concentric and eccen tric isokinetic contractions at velocities of 30-degrees, 90-degrees, 120-degrees, and 180-degrees/s. Isometric knee extensor torques, conce ntric knee extensor peak torques, and eccentric knee extensor peak tor ques were determined for each subject. Coefficients of determination ( r2) and linear regression equations were calculated to determine the s trength and nature of the relationships among the measurements. Result s. The coefficients of determination ranged from .60 to .94. Conclusio n and Discussion. The torque measurements were moderately to highly co rrelated, suggesting that the measurements obtained during different m aximal voluntary contractions may be assessing similar components of p erformance. [Kues JM, Rothstein JM, Lamb RL. The relationships among k nee extensor torques produced during maximal voluntary contractions un der various test conditions. Phys Ther. 1994;74:674-683.]