|
|
||||||||
Journal of Applied Physiology, Vol 72, Issue 5 1887-1894, Copyright © 1992 by American Physiological Society
ARTICLES |
J. E. Greenleaf, J. Vernikos, C. E. Wade and P. R. Barnes
Life Science Division, NASA Ames Research Center, Moffett Field, California 94035-1000.
Plasma and red cell volumes, body density, and water balance were measured in 19 men (32-42 yr) confined to bed rest (BR). One group (n = 5) had no exercise training (NOE), another near-maximal variable-intensity isotonic exercise for 60 min/day (ITE; n = 7), and the third near-maximal intermittent isokinetic exercise for 60 min/day (IKE; n = 7). Caloric intake was 2,678-2,840 kcal/day; mean body weight (n = 19) decreased by 0.58 +/- 0.35 (SE) kg during BR due to a negative fluid balance (diuresis) on day 1. Mean energy costs for the NOE, and IKE, and ITE regimens were 83 (3.6 +/- 0.2 ml O2.min-1.kg-1), 214 (8.9 +/- 0.5 ml.min-1.kg-1), and 446 kcal/h (18.8 +/- 1.6 ml.min-1.kg-1), respectively. Body densities within groups and mean urine volumes (1,752-1,846 ml/day) between groups were unchanged during BR. Resting changes in plasma volume (ml/kg) after BR were -1.5 +/- 2.3% (NS) in ITE, -14.7 +/- 2.8% (P less than 0.05) in NOE, and -16.8 +/- 2.9% (P less than 0.05) in IKE, and mean water balances during BR were +295, -106, and +169 ml/24 h, respectively. Changes in red cell volume followed changes in plasma volume. The significant chronic decreases in plasma volume in the IKE and NOE groups and its maintenance in the ITE group could not be accounted for by water balance or by responses of the plasma osmotic, protein, vasopressin, or aldosterone concentrations or plasma renin activity. There was close coupling between resting plasma volume and plasma protein and osmotic content.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
![]() |
C. E. Wade, K. I. Stanford, T. P. Stein, and J. E. Greenleaf Intensive exercise training suppresses testosterone during bed rest J Appl Physiol, July 1, 2005; 99(1): 59 - 63. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Shibasaki, T. E. Wilson, J. Cui, B. D. Levine, and C. G. Crandall Exercise throughout 6{degrees} head-down tilt bed rest preserves thermoregulatory responses J Appl Physiol, November 1, 2003; 95(5): 1817 - 1823. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. M. HASSER and J. A. MOFFITT Regulation of Sympathetic Nervous System Function after Cardiovascular Deconditioning Ann. N.Y. Acad. Sci., June 1, 2001; 940(1): 454 - 468. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Ohira, T. Yoshinaga, M. Ohara, I. Nonaka, T. Yoshioka, K. Yamashita-Goto, B. S. Shenkman, I. B. Kozlovskaya, R. R. Roy, and V. R. Edgerton Myonuclear domain and myosin phenotype in human soleus after bed rest with or without loading J Appl Physiol, November 1, 1999; 87(5): 1776 - 1785. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |