THE INFLUENCE OF VOLUNTARY UPPER-BODY EXERCISE ON THE PERFORMANCE OF STIMULATED PARALYZED HUMAN QUADRICEPS

In this study the influence of voluntary upper body exercise on the pe rformance of stimulated paralysed human quadriceps was investigated in five subjects with spinal cord lesions in the thoracic spine. The exp erimental set-up consisted of computer-controlled stimulation of the q uadriceps using electrodes on the surface of the skin, a dynamometer f or isometric or isokinetic loading of the lower leg, and a rowing ergo meter for upper body exercise. In all subjects, quadriceps fatigue tes ts were conducted to study the influence of upper body exercise on kne e torque during sustained continuous or intermittent stimulation of qu adriceps. The relative asymptotic torque appeared to be significantly higher with the presence of upper body exercise than without. This was consistently found both between trials (starting with or without uppe r body exercise) as well as within trials, when upper body exercise wa s started or stopped during the trial. No significant influence of upp er body exercise on the time constant of initial torque decline was fo und. (C) 1997 Elsevier Science Ltd.