TY - JOUR
T1 - Does resistance exercise prevent body fluid changes after a 90-day bed rest?
AU - Belin de Chantemele, Eric
AU - Blanc, Stéphane
AU - Pellet, Natacha
AU - Duvareille, Monique
AU - Ferretti, Guido
AU - Gauquelin-Koch, Guillemette
AU - Gharib, Claude
AU - Custaud, Marc Antoine
N1 - Funding Information:
Acknowledgements This study was sponsored by the European Space Agency, the National Space Development Agency of Japan and the Centre National d’Etudes Spatiales. CNES was the ‘‘promoteur’’ of the study according to French law. The study was performed by MEDES,the Institute for Space Physiology and Medicine. The authors would like to thank all the participants and the medical staff of the MEDES.
PY - 2004/8
Y1 - 2004/8
N2 - Although various exercise regimens are commonly used as countermeasures to reduce the cardiovascular deconditioning induced by microgravity, the underlying mechanisms are not well understood. In this study we aimed to test whether lower limb resistance exercise with flywheel technology can prevent the fluid homeostasis alterations induced by 90-day head-down tilt bed-rest (HDT), and thus improve orthostatic tolerance. Total body water (TBW, measured by isotope dilution) and plasma volume (PV, calculated from the haemoglobin and the haematocrit) were measured in a control group (Co, n=9) and a countermeasure group (CM, n=9). Simultaneously, plasma atrial natriuretic peptide (ANP), renin (AR), and aldosterone (Aldo), as well as urinary anti-diuretic hormone (ADH), were measured. Orthostatic tolerance was evaluated with a 10 min + 80° tilt-test the first day of recovery. After HDT, both groups showed a comparable decrease in orthostatic tolerance [8.2 (0.9) min, Co; 8.0 (0.7) min, CM], PV [-4.7 (1.8)%, Co; -6.2 (2.5)%, CM, P < 0.05] and TBW [-6.3 (5.4)%, Co; -3.7 (2.1)%, CM, P < 0.05]. AR [97.4 (22.0)%, Co; 117.3 (26.4)%, CM] and Aldo [111.3 (58.4)%, Co; 100.6 (52.0)%, CM] increased significantly in both groups but the countermeasures produced no noticeable effects [data are expressed as mean (SE)]. The drop in ANP was also similar in both groups [-42.0 (15.2)%, Co; -51.1 (27.7)% for the CM]. Surprisingly, urinary ADH declined similarly in both groups during the basal data control period [-25.3 (5.2)%, Co; -26.1 (9.6)%, CM) and was sustained at this level during the 90-day HDT. These results show that, under the conditions described, the flywheel exercise device failed to improve characteristic manifestations of cardiovascular deconditioning and suggest that more frequent and powerful exercise, associated with another device (e.g. LBNP) might be a better countermeasure.
AB - Although various exercise regimens are commonly used as countermeasures to reduce the cardiovascular deconditioning induced by microgravity, the underlying mechanisms are not well understood. In this study we aimed to test whether lower limb resistance exercise with flywheel technology can prevent the fluid homeostasis alterations induced by 90-day head-down tilt bed-rest (HDT), and thus improve orthostatic tolerance. Total body water (TBW, measured by isotope dilution) and plasma volume (PV, calculated from the haemoglobin and the haematocrit) were measured in a control group (Co, n=9) and a countermeasure group (CM, n=9). Simultaneously, plasma atrial natriuretic peptide (ANP), renin (AR), and aldosterone (Aldo), as well as urinary anti-diuretic hormone (ADH), were measured. Orthostatic tolerance was evaluated with a 10 min + 80° tilt-test the first day of recovery. After HDT, both groups showed a comparable decrease in orthostatic tolerance [8.2 (0.9) min, Co; 8.0 (0.7) min, CM], PV [-4.7 (1.8)%, Co; -6.2 (2.5)%, CM, P < 0.05] and TBW [-6.3 (5.4)%, Co; -3.7 (2.1)%, CM, P < 0.05]. AR [97.4 (22.0)%, Co; 117.3 (26.4)%, CM] and Aldo [111.3 (58.4)%, Co; 100.6 (52.0)%, CM] increased significantly in both groups but the countermeasures produced no noticeable effects [data are expressed as mean (SE)]. The drop in ANP was also similar in both groups [-42.0 (15.2)%, Co; -51.1 (27.7)% for the CM]. Surprisingly, urinary ADH declined similarly in both groups during the basal data control period [-25.3 (5.2)%, Co; -26.1 (9.6)%, CM) and was sustained at this level during the 90-day HDT. These results show that, under the conditions described, the flywheel exercise device failed to improve characteristic manifestations of cardiovascular deconditioning and suggest that more frequent and powerful exercise, associated with another device (e.g. LBNP) might be a better countermeasure.
KW - 90-day head-down tilt bed rest
KW - Cardiovascular hormones
KW - Flywheel exercise device
KW - Plasma volume
KW - Total body water
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U2 - 10.1007/s00421-004-1121-6
DO - 10.1007/s00421-004-1121-6
M3 - Article
C2 - 15170571
AN - SCOPUS:4544220559
SN - 1439-6319
VL - 92
SP - 555
EP - 564
JO - European Journal of Applied Physiology
JF - European Journal of Applied Physiology
IS - 4-5
ER -