[Stabilometry, Electromyography and Electroencephalography in Postmenopausal Women after Training of the Leg Support...

Ageing, lack of physical activity and sedentary lifestyle cause disorders of the sensorimotor system of postural control. The role of support afferentation in the changes in cortical activity in balance impairments has not been studied yet. The purpose of this study was to investigate the changes in the stabilographic parameters of the body center of gravity, alpha activity indices of the electroencephalography (EEG) and electromyographic (EMG) measurements of forehead muscle tone in response to visual activation in standing and sitting positions in postmenopausal women after and without training of leg support sensation (LSS) The variables were compared between 3 groups: Group A (n = 12, age: 66 ± 9 years)--women who have trained LSS with the help of Aikido techniques for 8 years; group F (n = 12, age: 65 ± 6 years)--women who have attended Fitness training for 8 years; group N (n = 11, age: 66 ± 7 years)--women who have not taken physical exercises for the last 8 years. It was found that in group N a change in body position from "sitting" to "standing" leads to a much greater increase in the area of stabilogram and in the energy expenditure needed to maintain the bal- ance than in groups A and F. Posture changes from sitting to standing position increases the tension of the forehead muscles and the suppression of alpha-1-amplitude, but decreases the power in high- and low-frequency alpha-band of EEG and the width of alpha-band in group N. In women ofgroup F the posture change does not result in an increase in EMG and signs of activation or tension in EEG; in group A it leads to a decrease of visual activation indices and psychoemotional tension and to an increase in power in alpha-2-band which is a sign of neuronal efficiency. Basing on these data, we can conclude that training focused on support afferentation in postmenopausal women decreases the psychoemotional tension and increases neuronal efficiency ofsensorimotor integration of postural control system and can be used in the prevention of falls in elderly people.