The Effect of Mental Practice on Increase of Strength and Electromyography Modification in Elbow Flexor Muscles

The purpose of the present study was to investigate the effects of mental practice on strength and electromyography modification of elbow flexor muscles. Sixteen healthy, untrained subjects (mean ± SD; age=22.5±1.36 years, height=175.18±6.62cm, weigh t=68.78±7.05 and movement imagery ability=20.81±3.71) participated in this study.Subjects were randomly assigned to a mental practice group (n = 8) or control group (n = 8). Mental practice group trained mental contraction of elbow flexion for 4 week (5 day per week); and control group was not trained but participated in all measurement. Mental practice program were included 50 mental maximal voluntary contractions for 2sets of 25 repetitions. Strength and electromyography was measured at pre and post training program. The t –student test was used to determine the statistical difference in variables of study in significant level of p􀂔0.05.The results showed that elbow flexion strength increased by 30 and 5 percent in mental practice and control groupsrespectively (p􀂔0.05). There was significantly difference between mental practice group and control group (p􀂔0.05). Also, EMG signals augmented significantly in elbow flexor muscle and decreased in elbow extensor muscle. It can be concluded that mental practice can increase strength elbow flexor muscles, which strength gain is attributed thetraining-induced changes in programming central nervous system and increases activation level muscle.