Bed Rest and Intermittent Centrifugation Effects on Human Balance and Neuromotor Reflexes.
Aerosp Med Hum Perform
; 88(9): 812-818, 2017 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-28818139
ABSTRACT
INTRODUCTION:
The effects of repeated centrifugation in association with head-down tilt (HDT) bed rest (BR) on the mediation of basic reflexes associated with the major postural muscles was investigated as a potential countermeasure for maintaining balance control and neuromotor reflex function.METHODS:
There were 15 male volunteers who were exposed to 21 d of 6° HDT-BR. Eight were treated with daily 1-h artificial gravity (AG) exposures aboard a short radius centrifuge that provided 1-g footward loading at heart level. The other seven served as HDT-BR control subjects. Balance control was assessed using a standard computerized dynamic posturography (CDP) protocol that was modified by adding low-frequency pitch-plane head movements. Neuromotor reflex function was assessed using tendon stretch reflexes (MSR) and functional stretch reflex (FSR) data collected from the triceps surae muscle group.RESULTS:
CDP performance was degraded by HDT-BR in both groups (ranging from 24 to 26%), but was unaffected by AG. BR also degraded MSR and FSR functions in both groups, with increased peak reflex latencies between 1.5 and 1.95 ms, but AG maintained pre-BR latencies for the MSR subjects.DISCUSSION:
AG exposure did not modify balance control from pre-BR responses, but did help prevent decrements in FSR latencies post-BR.Paloski WH, Reschke MF, Feiveson AH. Bed rest and intermittent centrifugation effects on human balance and neuromotor reflexes. Aerosp Med Hum Perform. 2017; 88(9)812-818.
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Base de dados:
MEDLINE
Assunto principal:
Reflexo de Estiramento
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Repouso em Cama
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Decúbito Inclinado com Rebaixamento da Cabeça
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Gravidade Alterada
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Equilíbrio Postural
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Intolerância Ortostática
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article