The effect of external attentional focus instructions with different distances on balance and muscular activity amongst children with mental retardation

Objective: The aim of this study was survey effect of distal and proximal external attentional focus instruction on postural sways and muscular electrical activity amongst children with mental retardation. Method: For this purpose, 30 child 10- 12 years old (M= 11.2) was selected from exceptional children schools and divided to three 10 persons groups (distal external attentional focus, proximal external attentional focus and control group) randomly. We used the Biodex Stability System to measure postural sways and Electromyogram to measure of muscular electrical activity. The participants at pre- test phase performed 10 trial (each trial was 20 second) without instruction, then each group in according with their group schedule participated in three training sessions (each session was 10 trials). Finally, the participants performed 10 trials without instruction as a post- test. During pre and post- test phases, the electrical activity of Soleus and Tibialis Anterior muscles was recorded. For intra- groups comparisons, paired t- test and covariance analysis and for between groups comparisons, ANOVA test was used. Results: The results show that the balance performance of distal external focus was better than other groups significantly. Also, the performance of proximal external focus group was better than the control group (P< 0/05). The comparisons of muscles electrical activity show that electrical activity of Soleus muscle in distal external focus group was less than proximal external focus group. But, in case of Tibialis Anterior muscles, the electrical muscle activity in two distal and proximal external focus group was less than control group significantly (P< 0/05). Conclusion: The findings of the present study show that shifting the attentional focus from away to closer distances has relatively better results on the balance and postural sways of children with mental retardation and support the constrained action hypothesis.