Measuring Quadriceps Muscle Activation During Isokinetic Contractions in Adults with Neuromotor Disorders Using the Interpolated Twitch Technique

What this Trial Is About

Researchers are investigating the voluntary activation of the quadriceps femoris muscle during subjectively maximal isometric and isokinetic concentric contractions in patients with various neurological and orthopedic conditions. The study focuses on how well muscle fibers are recruited during these contractions, especially since activation may be reduced in people with motor impairments such as hemiparesis post-stroke, multiple sclerosis, traumatic knee injuries, and knee osteoarthritis. The goal is to better understand muscle activation differences at varying joint rotation speeds in affected patients. Participants will perform isometric contractions at 40 knee flexion and isokinetic concentric contractions at an angular velocity of 100s using an isokinetic dynamometer. Voluntary activation will be measured using the interpolated twitch technique ITT, which involves delivering electrical shocks to the muscle belly during contractions to assess whether all muscle fibers are recruited. The procedure includes three electric shocks during isometric contractions and shocks during continuous passive motion and isokinetic concentric contractions, first on the affected limb and then on the non-affected limb. During the study, participants will undergo testing of muscle activation with electrical stimulation and perform specific knee movements. Researchers will measure voluntary activation levels as the primary outcome on the first day. Participants must be able to understand instructions, perform the motor tasks, and have sufficient knee joint mobility. The study also includes safety monitoring for conditions like epilepsy and other health factors that may affect participation. Total participation duration details are not specified.

Voluntary Activation During Isokinetic Contractions in Subjects with Neuromotor Disorders