Desenvolvimento do controle postural na senescência

• Ano de defesa: 2015
• Autor(a) principal: Silvana Lopes Nogueira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Senescência; Desenvolvimento motor; Dinâmica não-linear; Controle postural; Dinâmica não linear; Capacidade motora; Envelhecimento
• Link de acesso: http://hdl.handle.net/1843/BUOS-AQSJKU

Functional and anatomic changes in the many systems responsible for postural control happen over a lifetime and keep occurring during senescence. Postural control is essential for performing many daily activities, and has been studied through body sway. From the center of pressure, they draw up variables that inform about the magnitude (amount of variation) and structure (temporal organization) of body sway. One of the possible reasons for inconclusive results in the literature is the low demand offered by tasks in most of the studies comparing the young and the elderly, and in the few studies comparing the elderly at different ages. The aim of this study was to investigate the development of postural control during senescence, both in terms of magnitude and the structure of body sway. In Study 1, 15 young adults and 15 elderly were evaluated, with the purpose of verifying if the increase in task demand (basis of support) could point possible changes in the magnitude and structure of body sway with ageing. For this purpose, subjects were evaluated in three different basis of support (self-selected, feet together, semi-tandem). It was observed that increase in demand in the task extended the differences in the magnitude (amplitude and speed) of body sway between young adults and elderly, particularly towards the direction in which such constraint happened; but the same effect was not observed in the structure of sway between groups. In study 2, subjects of four age groups (young adults, young elderly, middle elderly and the oldest-old), with 15 subjects in each group, in the semi-tandem basis of support. It was verified that changes in the beginning of senescence were more related to the direction of task constraint (mediolateral), and such modifications were posteriorly maintained, there are also changes in the anteroposterior direction, first in speed and after in amplitude. Also, it was possible to observe that the elderly modified the emerging behavior in terms of the magnitude (amount) of sway, but the structure of sway pattern remained similar between the studied groups. It was concluded that the development of postural control through aging, specially in senescence, occurs in a different manner in anteroposterior and mediolateral directions, and that the changes in behavior in order to reach the postural stability, affects the magnitude of body sway more. However, the structure of sway is similar over time.