F-wave study at different stimulation rates.

In 50 ulnar nerves of healthy subjects, F-wave latency, duration, amplitude and persistence were determined at different frequencies of the antidromic impulse (0.2-0.5-1-2 Hz). The F amplitude and persistence were found significantly increased at higher stimulation rates, suggesting that the frequency of the antidromic impulse influences the motoneuron pool discharges. Individual cross-correlation values (r) obtained for latency and duration, latency and amplitude, amplitude and duration did not show any significant changes at different stimulation rates.