عنوان مقاله [English]
Background and Aim: Reaching is one of the common daily life tasks. Most of daily life activities, such as reaching, are performed simultaneously by cognitive tasks, and thus result in decline in performance of the main tasks. The aim of the present study was to investigate the effect of constant (simple reaction time) and random variable (choice reaction time) trainings on anticipatory postural adjustment under dual task conditions.
Materials and Methods: A total of 16 right handed young girls with an average age of (27.18± 3.18) participated in the current pre-test, post-test randomized group design research. To evaluate magnitude of anticipatory postural adjustment, center of pressure displacement and center of pressure mean velocity were measured using force plate before reaching movement initiation under dual task conditions. Data was analyzed using Matlab and SPSSS softwares.
Results: The results of independent t-test of pre-test and post-test scores showed that, in constant training, mean velocity of center of pressure was greater than that of random variable training. Also, 2×2 combine variance analysis in the center of pressure displacement did not show significant differences between the two groups
Conclusion: According to the results, after constant training, anticipatory postural adjustment is improved under dual task conditions. This type of training leads to improvement of anticipatory postural adjustment after internal perturbation. Findings of the present study support Task-specific practice hypothesis evidence.
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