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Background and aim: To investigate the effect of the light touch, vision and dual task interference on the surface electromyography (sEMG) activity of ankle muscles Participants: Thirty persons (12 male, 18 Female), right hand without any neuro-musculo-skeletal disorder and in healthy condition, participated in this study.
Methods and Materials: Participants stood in upright and semi tandem position. There was a high sensitivity sensor on the right side in direction of femur greater trochanter. They should press the sensor less than 50 gr. Also we examined the rate of activity in 3 muscles (Tibialis Anterior, Proneus Longuse, Soleuse) on both lower limbs by Biometrix sEMG device. 4 positions were experimented in semi tandem standing: No Touch, No Counting No Touch, Counting Light Touch, No Counting Light Touch, Counting. Each of the above positions was tested in 2 conditions: Eyes Open, Eyes Closed.
Results: Our findings detect that light touch contact especially during vision, resulted in reducing the rate of sEMG activity in the leg postural muscles. No touch and closed eyes, raise the rate of sEMG activity to maximum.
conclusion: On basis of findings, it seems that following skin receptors stimulation, some complicated mechanisms will be begun and in order to the orders of Central Nervous System (CNS), these muscles will make the hole body, stable. So it can reduce the entered pressure on leg postural muscles. Therefore we can see the lesser rate in sEMG activity of leg postural muscles.