Inhibitory effect of unilateral contraction on the contralateral arm

Electromyograms of the triceps and biceps brachii of both arms of 6 subjects were recorded in reaction trials to flashing stimulus. Rapid voluntary elbow extension was immediately preceded by a silent period of the unexercised contralateral agonist (contralateral agonist silent period). Since this silent period was not accompanied by a contralateral antagonist contraction, the contralateral agonist silent period was not attributable to reciprocal inhibition in the spinal levels.