Linked Life Data

3711981

Source:http://linkedlifedata.com/resource/pubmed/id/3711981

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1986-7-1
pubmed:abstractText
Experiments were done to determine the amplitude of the monosynaptically mediated H-reflex of the soleus muscle at various phases of the step cycle, using a computer-based analysis procedure. In all subjects tested the amplitude of the H-reflex was strongly modulated in amplitude during the walking cycle and was highest during the stance phase. In many subjects the peak reflex amplitude occurred at about the same time as the peak soleus electromyographic (EMG) activity, but in others it occurred earlier. The form of the reflex variation (i.e., envelope of H-reflex amplitude versus phase in cycle) during the step cycle could also be quite different from that of the EMG produced during stepping. At an equal stimulus strength and EMG level, the H-reflex was always much larger, up to 3.5 X, during steadily maintained contractions while standing than during walking. The large reflexes when subjects were standing are consistent with the control of position required to maintain a stable posture in this task. Similarly, the reflexes during walking are greatest during the stance phase, when they will assist in maintaining the upright position of the body against gravity. The reflexes are smallest during the swing phase when they would oppose ankle flexion. However, since the reflex amplitude is task-dependent (i.e., greater during standing than during walking at the same EMG and stimulus levels) and is not always closely related to the EMG produced during a given task such as walking, the strong modulation of H-reflex during walking is not simply a passive consequence of the alpha-motoneuron excitation level.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0270-6474
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1308-13
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Amplitude modulation of the soleus H-reflex in the human during walking and standing.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't