Investigating the Impact of Dual Task Condition and Visual Manipulation on Healthy Young Old During Non-Dominant Leg Stance

Objectives: The dominant leg has always received special attention in public health practices and even in professional clinical evaluation and interventions. The aim of this research study was to methodically examine the substrate balance character of the non-dominant leg under dual task conditions and visual deprivation to increase the baseline insight for maintaining body balance and for fall prevention in aging adults. Methods: Twenty healthy senior citizens with non-dominant left leg were conscripted into a cross-sectional study, the aim of which was to examine one-legged standing balance strategy on a force plate at Motor Control Laboratory in University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. Four balance conditions with varied levels of difficulty, including: (a) single left leg standing with open eyes; (b) single left leg standing with open eyes performing Stroop dual task; (c) single left leg standing with eyes shut; and (d) single left leg standing with eyes shut under dual task condition. These conditions were applied to assess balance function of the non-dominant leg of the subjects.  Results: Repeated measurement tests revealed that among the six variables, namely Area, Mean Velocity, Range Fore After, Range Side Way, Entropy X, and Entropy Y, that are measured by force plate, only Entropy X did not have a significant difference between conditions (P<۰.۰۵). Discussion: Standing on non-dominant leg is a challenging task that requires a well-balanced system to survive the primary decreased somatosensory input. Therefore, the examinee had to have the requisite capabilities to cope with the changes caused when extra manipulation was included. During the course of the study, the most challenging situation was encountered when the subjects were standing on their non-dominant leg with eyes shut, which should be exactingly checked not to create a risky point as an Achilles’ heel of balance system. It was observed that the non-dominant leg was more susceptible to be affected when an aging adult did not have access to the visual input or during performing dual tasks with eyes shut. It is thus recommended that such conditions should be included in balance assessment tests or interventions.

Keywords:

Geriatric , Postural equilibrium , Stroop test