Voluntary Activation During Isokinetic Contractions in Subjects with Neuromotor Disorders

"Voluntary Activation level will be determined according to the interpolate twitch technique (ITT).~During isometric contractions (knee at 40° flexion), three electric shocks (doublets) will be delivered. The first shock will be delivered at rest before contraction. The second one will be delivered 3-4 s after the beginning of the effort. The third one will be delivered at rest 2-3 s after the contraction has ended. Two isometric contractions will be performed, with a 3-minute break.~Then, 3 consecutive continuous passive motion (CPM) extension-flexions of the knee joint (range 105-0°), and 3 isokinetic concentric contractions (ISOK) will be performed. During both CPM and ISOK an electric shock will be delivered during each repetition. The instant of stimulation will be determined in a way allowing the twitch moments to peak at exactly 40° of knee flexion during extension. The same procedure will be administered first to the affected limb, and then to the non-affected limb."