Some of the cardiovascular changes associated with spaceflight have similarities to those associated with aging. We studied the neuroendocrine and hemodynamic responses to upright posture in a 77 year old astronaut before and after spaceflight and compared them to those of a group of 20 younger (41 plus or minus 1 years) astronauts. While arterial pressure responses to standing were similar between the young and old astronauts, hemodynamic profiles were quite different. The elderly astronaut achieved adequate standing arterial pressure primarily by maintaining stroke volume and thus cardiac output. In spite of very high norepinephrine release, he had very little increase in heart rate or total peripheral resistance. This pattern persisted on all test occasions. These responses suggest high sympathetic responses, down-regulated adrenergic receptors and decreased venous compliance typical of aging. In contrast, younger astronauts did not maintain stroke volume or cardiac output with standing, but had significant increases in heart rate and resistance. These results suggest that this elderly subject had cardiovascular responses to standing that are expected in an aged person. These responses were not deleteriously affected by spaceflight. We suggest that healthy, fit elderly individuals are able to withstand the stresses of extreme environments and are not necessarily limited in their activities simply due to their chronological age.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    Spaceflight Did Not Impair Cardiovascular Responses to Upright Posture in an Elderly Astronaut


    Contributors:
    A. C. Rossum (author) / M. G. Ziegler (author) / J. V. Meck (author)

    Publication date :

    2001


    Size :

    32 pages


    Type of media :

    Report


    Type of material :

    No indication


    Language :

    English




    Spaceflight Did Not Impair Cardiovascular Responses to Upright Posture in an Elderly Astronaut

    Rossum, Alfred C. / Ziegler, Michael G. / Meck, Janice V. | NTRS | 2001



    Government Astronaut Participation In Suborbital Spaceflight

    B. T. Hill / E. Blome / R. W. Seibold | NTIS | 2021


    Government Astronaut Participation In Suborbital Spaceflight

    Bradley T. Hill / Elizabeth Blome / Robert W. Seibold | NTRS