Ajuste postural no processo de equilíbrio instável em indivíduos com privação momentânea da visão

Abstract

The postural control is essential to voluntary motor acts, and daily life activities. The CNS (Central Nervous System) has many strategies to maintain the body equilibrium against the gravity. The objective of this study was to evaluate the effect on anticipatory postural adjustment (APA) and compensatory postural adjustment (CPA) in the Instantaneous Point of Equilibrium (IPE). Kinematics and kinetic resources have been used to locate IPE at upright posture. The subjects were 1O young adult without any orthopedicor neurologic injury or disease mean age = 25, 6 ± 2, 26 years; mean weight = 68, 22 ± 2, 71 kg; mean height = 1, 69 ± 0, 25 m. The EMGs of six right side muscles were measured with surface, disposable, differential monopolar electrodes. The motor task was fast trunk extension, from 90 degrees flexion to the upright posture. We calculate the variables APA and CPA from EMGs of some trunk and lower limbs muscles. The preliminary results show that vision is important for modulating muscle activity amplitude during APA and APC, as it seems that non-visual sensory information could not fully compensate for the lack of continuous visual feedback. © Springer-Verlag Berlin Heidelberg 2007.