Neural Mechanisms Influencing Interlimb Coordination during Locomotion in Humans: Presynaptic Modulation of Forearm H-Reflexes during Leg Cycling
Figure 5
Effect of superficial radial nerve conditioning on flexor carpi radialis (FCR) H-reflex amplitudes during leg cycling.
(A) Rectified and averaged FCR EMG and H-reflex waveforms following superficial radial (SR) nerve stimulation [1.0× radiating threshold (RT)] obtained from a single subject. (B) Conditioning effect of FCR H-reflex with weak radial nerve stimulation (0.51×RT) during static and cycling tasks. (C) EMG responses following weak SR nerve stimulation (0.51×RT; just above perceptual threshold) during static activation and leg cycling. Please note that figures 5A, B, and C were obtained from same subject. (D) Grand means (± SEM) of H-reflexes (upper panel), M-waves (middle panel), and pre-stimulus EMG levels (lower panel) in the FCR muscle during SR nerve conditioning obtained from 9 subjects. * p<0.01 significantly different from the unconditioned values of each tasks. +p<0.01 significantly different from the unconditioned static values. Format and abbreviations as in Figure 4.