I Urzica1, V Tiffreau, S Popielarz, B Duquesnoy, A Thevenon. 1. Service de médecine physique et de réadaptation, centre hospitalier régional universitaire de Lille, rue du Professeur-A.-Verhaeghe, 59037 Lille cedex, France.
Abstract
UNLABELLED: Isokinetic dynamometers put subjects in very different conditions from natural movement. Familiarization with the isokinetic device may therefore explain better performance without showing any improvement in strength. OBJECTIVE: To determine the part of habituation and training in improved trunk isokinetic performance on isometric assessment after a back rehabilitation program for chronic low back pain. METHODS: A total of 26 patients with chronic low back pain consecutively admitted to the same rehabilitation department for a 4-week rehabilitation program underwent isometric assessment of the trunk flexors and extensors on the day of admission and 2 days and 21 days after admission. The maximal torque and total work were registered at 30 degrees , 90 degrees and 120 degrees/s. RESULTS: Values for all parameters, except flexor values at 30 degrees/s, were significantly improved between day 0 and day 2 after admission. Between day 2 and day 21 after admission, values for all parameters were improved significantly. Except for flexor values at 30 degrees/s, the parameter values at day 2 showed improvement ranging from 33% to 58% of the improvement seen at day 21. DISCUSSION: The improvement in parameter values found on isokinetic assessment two days after a one-day rehabilitation program for low back pain is probably explained by a habituation effect. We can expect that increase in the maximal torque and total work after 3 weeks of rehabilitation is, at least in part, the consequence of the strengthening program. CONCLUSION: We should interpret with caution the results of studies involving an isokinetic dynamometer to measure the strength of trunk muscles without a learning training.
UNLABELLED: Isokinetic dynamometers put subjects in very different conditions from natural movement. Familiarization with the isokinetic device may therefore explain better performance without showing any improvement in strength. OBJECTIVE: To determine the part of habituation and training in improved trunk isokinetic performance on isometric assessment after a back rehabilitation program for chronic low back pain. METHODS: A total of 26 patients with chronic low back pain consecutively admitted to the same rehabilitation department for a 4-week rehabilitation program underwent isometric assessment of the trunk flexors and extensors on the day of admission and 2 days and 21 days after admission. The maximal torque and total work were registered at 30 degrees , 90 degrees and 120 degrees/s. RESULTS: Values for all parameters, except flexor values at 30 degrees/s, were significantly improved between day 0 and day 2 after admission. Between day 2 and day 21 after admission, values for all parameters were improved significantly. Except for flexor values at 30 degrees/s, the parameter values at day 2 showed improvement ranging from 33% to 58% of the improvement seen at day 21. DISCUSSION: The improvement in parameter values found on isokinetic assessment two days after a one-day rehabilitation program for low back pain is probably explained by a habituation effect. We can expect that increase in the maximal torque and total work after 3 weeks of rehabilitation is, at least in part, the consequence of the strengthening program. CONCLUSION: We should interpret with caution the results of studies involving an isokinetic dynamometer to measure the strength of trunk muscles without a learning training.