ANTHROPOMETRIC VARIABLES, SELF-EFFICACY BELIEFS, AND PAIN AND DISABILITY RATINGS ON THE ISOKINETIC PERFORMANCE OF LOW-BACK-PAIN PATIENTS

Objectives. This study investigated how age, sex, height, body weight, self-efficacy beliefs, pain, and subjective disability predict the pe rformance of low back pain patients on an isokinetic trunk muscle test . Methods. One hundred and five patients participated in the study. De pendent variables were isokinetic flexion and extension strength measu red as total work done at speeds 50, 100, and 150 degrees/second. Resu lts. The anthropometric measures were poor predictors, height being th e only significant one. Body weight and age were of no relevance for t he performance. Subjective pain and disability had negative effects on the performance of men, but not of women. Self-efficacy beliefs, i.e. , the patient's belief in his or her capability to endure physical act ivities, was the most powerful predictor. Conclusion. For the purpose of validation, standardization, and interpretation of isokinetic perfo rmance in low back pain patients, these factors should be taken into a ccount.