Acessibilidade / Reportar erro

Use of the anchor system with both hands, and with the non-dominant hand reduces body oscillation in older adults

Abstract

The purpose of this study was to compare the effect of using the anchor system bilaterally and unilaterally (dominant and non-dominant hands), in older adults, in two visual conditions (with and without vision). Fourteen older adults were positioned in a semi-tandem position on a force plate, where they performed tasks under eight experimental conditions that employed the anchor system (two-handed, dominant hand, non-dominant hand, and without anchor), both with and without vision. The results, illustrated through the ellipse area adjusted to the displacement of the center of pressure (COP) and the mean sway velocity of the COP, showed that tasks performed with the anchor system held by both hands, and the anchor system held by the non-dominant hand, reduced both body sway and velocity when compared to the condition without the anchor. Furthermore, the task conditions with vision also reduced the ellipse area and the mean sway velocity. Overall, the anchor system is a tool that effectively allowed the older adults to decrease body sway. The effect of adding haptic information was similar throughout the different visual conditions tested, suggesting that the additional haptic information provided by the anchor system had a constant impact and did not vary with changes in the availability of vision. These results add new insights to the field of haptics when compared to findings of previous studies that use the light touch paradigm. Differences between the paradigms of light touch and the anchor system-and inter-hemispheric asymmetries in haptic perception tasks-were used to explain these insights.

KEY-WORDS:
Haptic information; Hand dominance; Control of posture; Aging

Escola de Educação Física e Esporte da Universidade de São Paulo Av. Prof. Mello Moraes, 65, 05508-030 São Paulo SP/Brasil, Tel./Fax: (55 11) 3091 3147 - São Paulo - SP - Brazil
E-mail: reveefe@usp.br