Muscular fatigue: isokinetic and Electromyographic Analysis of the flexion and extension movements of the elbow of typical children and adolescents

Abstract

Muscular fatigue is a symptom observed in chronic diseases affecting children and adolescents related to factors as age, sex, body composition and sexual maturation. It interferes in the everyday tasks, impairing the subjects' quality of life and functional capacity. However, the methodology used to evoke fatigue in muscular groups of the upper limbs of children and adolescents is little explored in the scientific literature. Objective: To identify the occurrence of fatigue during elbow flexion and elbow Extension movements of typical children and adolescents at different velocities by means isokinetic (Biodex Mult Joint System 4®) and electromyographic (Delsys Trigno®) evaluation. Methods: 30 subjects (8to 16 years) of both sexes and diferente levels of sexual maturation, will participate. The evaluation will be composed by the measurement of body mass, height, body composition, level of Physical activity and level of sexual maturation. Participants will be positioned on the dynamometer chair and surfasse electrodes will be placed on the biceps and tríceps brachii muscles. The simultaneous, isokinetic and electromyographic evaluation will comprise the execution of concentric movements of elbow flexion and Extension at velocities 120 and 180°s-1, randomly selected, and with unlimited repetitions until the participant reaches fall of 50% of the maximum force with a rest of 5 minutes between speeds. Before and after each stage of the Isokinetic evaluation, the Borg CR-10 scale will be applied. The Isokinetic variables will be analyzed: peak torque and work, and electromyographic variables: signal amplitude and median frequency.