A study to examine the effect of electrical stimulation of sensory nerves in the arm on motor nerve excitation

INTERVENTION: Electrical stimulation is performed by changing the stimulation conditions (frequency and stimulation time). Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. Three random conditions are selected out of nine combinations of frequency (1, 10, and 50 Hz) and stimulation time (20, 40, and 60 min) for every case. CONDITION: Healthy adults PRIMARY OUTCOME: Motor evoked potential ratio INCLUSION CRITERIA: