Carotid artery blood flow and middle cerebral artery blood flow velocity during physical exercise.
J Appl Physiol (1985)
; 81(1): 413-8, 1996 Jul.
Article
em En
| MEDLINE
| ID: mdl-8828693
ABSTRACT
Factors controlling cerebral blood flow (CBF) during exercise are complex and incompletely known. Different techniques have shown partly contradictory results of changes in regional and global cerebral perfusion during dynamic exercise in healthy subjects. To elucidate the global CBF response to supine stepwise increasing physical exercise, we measured blood flow in the left common carotid artery (QCCA) and the left internal carotid artery (QICA) simultaneously with the blood flow velocity in the ipsilateral middle cerebral artery (VMCA) using duplex ultrasonography and transcranial Doppler ultrasonography. During moderate exercise intensity (60-67% of maximal capacity), the VMCA increased 14% (P < 0.001), the QICA 17% (P < 0.01), and the QCCA 33% (P < 0.001) compared with baseline values. High physical exercise intensity (80-90% of maximal capacity) tended to reduce VMCA and QICA compared with moderate exercise, in contrast to a continued increase in QCCA. The results indicate an increased global CBF during exercise. This increase was reduced during hard exercise due to a decrease of the arterial PCO2 secondary to hyperventilation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Exercício Físico
/
Artérias Carótidas
/
Artérias Cerebrais
/
Circulação Cerebrovascular
Limite:
Adult
/
Humans
/
Male
Idioma:
En
Revista:
J Appl Physiol (1985)
Assunto da revista:
FISIOLOGIA
Ano de publicação:
1996
Tipo de documento:
Article
País de afiliação:
Suécia