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Updated: Jul 22, 2026

Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy
Published on: February 20, 2018
Unloading reflex of a hand muscle
1Department of Neurology, Veterans Administration Medical Center, Palo Alto, CA 94304.
Abstract:
The unloading reflex of abductor hallucis brevis was elicited by removal of the external load during voluntary contraction. The duration of the unloading pulse was varied experimentally from 1 to 32 msec. With all stimulus durations, the response was a measurable decrease in the level of EMG activity. Expressed as a percentage change from baseline, the mean size of the unloading reflex was a logarithmic function of the unloading pulse duration. The results demonstrate that the hand muscles are sensitive to very brief mechanical stimuli. Although the motoneurons of the intrinsic hand muscles receive strong projections from the cerebral cortex, they exhibit reflex behavior similar to that of the large, postural muscles.
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