Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1992-5-12
pubmed:abstractText
Equilibrium is ensured during forward or backward upper trunk movements by displacing the hip and knee simultaneously in opposite directions. When fast movements are performed, a muscle synergy characterized by the early activation of a set of trunk, thigh and leg muscles precedes the onset of the kinematic changes. The question which is addressed concerns the possibility that two levels of equilibrium control might exist during upper trunk movements: the strategy level, which is relatively invariant, is characterized by the displacement in opposite directions of the upper and low segments, and the muscle synergy level at which the strategy is implemented, which may be adaptable to the environmental constraints. When upper trunk movements are performed under microgravity with the subject's feet fixed to the floor of the space cabin, the displacement of upper and lower body segments in opposite directions still occurs, although this is no longer necessary to maintain the equilibrium. This kinematic strategy seems to be aimed at regulating the centre of inertia position with respect to the feet. The muscle synergies associated with these kinematic changes are modified, however, under microgravity. After returning to the ground, the previous synergies do not reappear immediately, but only after a few days. This suggests that a short period of learning is needed to change the synergy. These data are compatible with the hypothesis that two levels of equilibrium control actually exist during upper trunk movements, the strategy level, which is kinematic and invariant, and the synergy level, which is adaptable to the environmental constraints through a short learning process.
pubmed:language
fre
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0764-4469
pubmed:author
pubmed:issnType
Print
pubmed:volume
314
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
87-92
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
[Strategy and synergy: two levels of equilibrium control during movement. Effects of the microgravity].
pubmed:affiliation
Laboratoire de Neurosciences fonctionnelles, C.N.R.S., Marseille.
pubmed:publicationType
Journal Article, English Abstract