Angle-specific torques of thigh muscles: variability analysis in 200 healthy adults.

This study evaluated the variability of the isokinetic angle-specific torques (ASTs) at 15 and 75 degrees of knee flexion and assessed the relationship between them and the isokinetic peak torque (PT) in 200 healthy adults. The results showed that the value of these AST measurements was lower than of the PT measurements. This was due to larger variability of the AST (male and female coefficient of variation [cv] 34 and 43% in the ASTs vs. 19 and 31% in the PTs); unequal variation in the results between men and women (mean cv 27% in men vs. 34% in women); and fairly poor prediction of the ASTs from the PT (PT accounted for only 39 and 62% for the variation seen in the men's and women's AST results). Furthermore, in regression analysis the standard errors of the estimates were unacceptably high, averaging 26%. AST measurements should not be used routinely.