Seyed Mohammad Niazi, Nasser Bai and Minoo Dadban Shahamat
The purpose of the present study was to Investigation the effect of mental imagery training on electrical fluctuation of muscles motor units and muscles strange in lower limb. 30 healthy, previously untrained subjects (mean ±SD; age =22.4±1.25years, height=176.18±5.62cm, weight=67.65±6.15) participated in this study. Subjects were randomly assigned to a mental practice group (n=15) or control group (n=15). Mental practice group trained mental contraction of plantar flexion movement for 4 weeks (5 day per week): and control group was not trained but participated in all measurement. Practice program were included 50 mental maximal voluntary contractions for 2 sets of 25 repetitions. Strength and electromyography of the gastronomies (GAS) and tibialis anterior (TA) muscle was measured at pre- post test. To determine the statistical difference in variables of the study the t-student test was used in significant level of P≤0.05. The results of this study indicated that mental practice group significantly increased their plantar flexor maximal voluntary contraction (MVC) but was not significantly in control group (p ≤.05). Also mental practice group significant increased their gastronomies muscle EMG but was not significant in control group (p ≤.05). Also the results of this study indicated that the tibialis anterior muscle EMG significantly decreased in mental practice group but was not significant in control group (p ≤.05). We concluded that mental practice can increase strength plantar flexor muscle, which strength gain is attributed the training-induced changes in programming central and increases activation level of agonist muscle and decreases of them in antagonist muscle. Results showed that the effect of imagery training on athletic performance has been very effective.
