Efeito do treinamento de força muscular nas estratégias de controle motor utilizadas por indivíduos com síndrome de Down

Abstract

Introduction: During the performance of upper arm movements with reversal, individuals with Down syndrome are slow and clumsy. One explanation for this behavior is the difficulty of these individuals to coordinating muscle torques generated on shoulder and elbow joints. Purpose: To test the hypothesis that the increase on muscle force, obtained by a weight training protocol validated to this population, would be reflected on improvements in terms of motor performance (i.e. speed) during the performance of upper arm movements with reversal. This improvement would be explained by changes on the strategies to generated and coordinated torques on the shoulder and elbow joints. Methods: Before and after the period of training, individuals with Down syndrome also participated of upper-arm movements with reversal test. The movements of shoulder and elbow joints were reconstructed using Optotrak (3020) system and the muscle and interaction torque for both joints were calculated using Dynamical Inverse. Results: The training protocol used here was efficient to increase muscle force in individuals with Down syndrome and movement speed. The increase of speed during the movement to the target was obtained by increasing the shoulder muscle torque and the elbow interaction torque. The increase of speed during the movement to the initial position was obtained by improvements on the coupling between these torques, despite of only one strategy has not been observed. Conclusion: This study reinforces the hypothesis that Down syndrome individuals can benefit of weight training protocol to improve motor performance.