Zenon Silva

Electromyographic evaluation of upper limb muscles involved in armwrestling sport simulation during dynamic and static conditions

OBJECTIVE To evaluate the electromyographic activity of the Pectoralis Major (PM), Biceps Brachii (BB), Pronator Teres (PT) and Flexor Carpi Ulnaris (FCU) muscles involved in simulated armwrestling. METHODS Ten trained volunteers were selected to perform the armwrestling movement, during dynamic tests with 40% and 80% of maximum voluntary load (MVL) and static tests in the initial, intermediary and final positions. Electromyographic and force data were normalized for analyses. RESULTS In dynamic tests with 40% MVL, electric activity of the PT muscle was greater than FCU (p<0.01) and BB (p<0.05) muscles, and with 80% MVL, PM and PT muscles were the most active. In static tests, electric activity increased from the initial to final positions for the PM muscle (p<0.05), while it decreased for the BB and PT muscles (p<0.001 and p<0.05, respectively). No significant changes were observed for force and no correlation was found with the simultaneous electric activity. CONCLUSIONS It can be concluded that the PM and FCU muscles participate as agonists in the simulated armwrestling whereas the BB and PT muscles seem to perform secondary functions. Electric activity showed to be dependent on the load and on the position of the upper limb, but not on the force produced during the movement.