Abstract
[Purpose] We investigated the excitation levels of spinal motoneurons of the upper limbs during walking in healthy subjects using F waves as a piece of basic research in order to validate the neurophysiological mechanism behind the associated reaction in stroke patients. [Subjects] The subjects were 30 healthy men aged 24.0±5.9 years. [Method] We recorded F waves (frequency, F/M amplitude ratio and latency) in the thenar muscle of the upper arm preceding, during, just after and 1 and 2 min after walking. [Results] F wave frequency changed significantly during walking, but the F/M amplitude ratio and latency did not show any significant changes. [Conclusion] These finding indicate that the excitability of the spinal motoneurons of the upper limbs of healthy subjects had a tendency to increase during walking. From this, we reason that excitation of the spine at the levels of the upper arm muscles also increases in stroke patients during walking, and that this needs to be considered when making treatment plans for them.
