Signals consistent with microbubbles detected in legs of normal human subjects after exercise.
J Appl Physiol (1985)
; 108(2): 240-4, 2010 Feb.
Article
en En
| MEDLINE
| ID: mdl-19875715
ABSTRACT
Exercise may produce micronuclei (presumably gas-filled bubbles) in tissue, which could serve as nucleation sites for bubbles during subsequent decompression stress. These micronuclei have never been directly detected in humans. Dual-frequency ultrasound (DFU) is a resonance-based, ultrasound technique capable of detecting and sizing small stationary bubbles. We surveyed for bubbles in the legs of six normal human subjects (ages 28-52 yr) after exercise using DFU. Eleven marked sites on the left thigh and calf were imaged using standard imaging ultrasound. Subjects then rested in a reclining chair for 2 h before exercise. For the hour before exercise, a series of baseline measurements was taken at each site using DFU. At least six baseline measurements were taken at each site. Subjects exercised at 80% of their age-adjusted maximal heart rate for 30 min on an upright bicycle ergometer. After exercise, the subjects returned to the chair, and multiple postexercise measurements were taken at the marked sites. Measurements continued until no further signals consistent with bubbles were returned or 1 h had elapsed. All subjects showed signals consistent with bubbles after exercise at at least one site. The percentage of sites in a given subject showing signals significantly greater than baseline (P < 0.01) at first measurement ranged from 9.1 to 100%. Overall, 58% of sites showed signals consistent with bubbles at the first postexercise measurement. Signals decreased over time after exercise. These data strongly suggest that exercise produces bubbles detectable using DFU.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Ejercicio Físico
/
Gases
/
Pierna
Tipo de estudio:
Diagnostic_studies
Límite:
Adult
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Appl Physiol (1985)
Asunto de la revista:
FISIOLOGIA
Año:
2010
Tipo del documento:
Article
País de afiliación:
Estados Unidos