Cardiovascular determinants of maximal oxygen consumption in upright and supine posture at the end of prolonged bed rest in humans

被引:23
作者
Bringard, Aurelien [1 ]
Pogliaghi, Silvia [2 ]
Adami, Alessandra [1 ,2 ]
De Roia, Gabriela [2 ]
Lador, Frederic [3 ]
Lucini, Daniela [4 ]
Pizzinelli, Paolo [4 ]
Capelli, Carlo [2 ]
Ferretti, Guido [1 ,5 ]
机构
[1] Ctr Med Univ Geneva, Dept Neurosci Fondamentales, CH-1211 Geneva 4, Switzerland
[2] Univ Verona, Fac Sci Esercizio & Sport, I-37131 Verona, Italy
[3] Hop Univ Geneva, Div Pneumol, Dept Med Interne, CH-1211 Geneva 4, Switzerland
[4] Univ Milan, Ctr Terapia Neurovegetat, Dipartimento Sci Clin, Osped L Sacco, I-20157 Milan, Italy
[5] Univ Brescia, Dept Biomed Sci & Biotechnol, I-25123 Brescia, Italy
基金
瑞士国家科学基金会;
关键词
Exercise capacity; Cardiac output; Cardiovascular response; Simulated microgravity; CARDIAC-OUTPUT; EXERCISE PERFORMANCE; O-2; CONSUMPTION; BLOOD-FLOW; RESPONSES; INACTIVITY; CAPACITY; BEDREST; VOLUME; NORADRENALINE;
D O I
10.1016/j.resp.2010.03.018
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
We tested the hypothesis that, after bed rest, maximal oxygen consumption ((V) over dot(O2max)) decreases more upright than supine, because of adequate cardiovascular response supine, but not upright. On 9 subjects, we determined (V) over dot(O2max) and maximal cardiac output ((Q) over dot) upright and supine, before and after (reambulation day upright, the following day supine) 35-day bed rest, by classical steady state protocol. Oxygen consumption, heart rate (f(H)) and stroke volume (Q(st)) were measured by a metabolic cart, electrocardiography and Modelflow from pulse pressure profiles, respectively. We computed (Q) over dot as f(H) times Q(st), and systemic oxygen flow ((Q) over dota(O2)) as (Q) over dot times arterial oxygen concentration, obtained after haemoglobin and arterial oxygen saturation measurements. Before bed rest, all parameters at maximal exercise were similar upright and supine. After bed rest, (V) over dot(O2max) was lower (p < 0.05) than before, both upright (-38.6%) and supine (-17.0%), being 30.8% higher supine than upright. Maximal Q(st) decreased upright (-44.3%), but not supine (+3.7%), being 98.9% higher supine than upright. Maximal (Q) over dot decreased upright (-45.1%), but not supine (+9.0%), being higher supine than upright (+98.4%). Maximal (Q) over dota(O2) decreased upright (-37.8%), but not supine (+14.8%), being higher (+74.8%) upright than supine. After bed rest, the cardiovascular response (i) did not affect (V) over dot(O2max) supine, (ii) partially explained the (V) over dot(O2 max) decrease upright, and (iii) caused the (V) over dot(O2 max) differences between postures. We speculate that impaired peripheral oxygen transfer and/or utilisation may explain the (V) over dot(O2max) decrease supine and the fraction of (V) over dot(O2max) decrease upright unexplained by cardiovascular responses. (C) 2010 Elsevier B.V. All rights reserved.
引用
收藏
页码:53 / 62
页数:10
相关论文
共 50 条
  • [21] FACTORS LIMITING MAXIMAL O-2 CONSUMPTION - EFFECTS OF ACUTE CHANGES IN VENTILATION
    FERRETTI, G
    DIPRAMPERO, PE
    [J]. RESPIRATION PHYSIOLOGY, 1995, 99 (02): : 259 - 271
  • [22] Maximal O2 consumption: Effects of gravity withdrawal and resumption
    Ferretti, Guido
    Capelli, Carlo
    [J]. RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY, 2009, 169 : S50 - S54
  • [23] Prolonged head down bed rest-induced inactivity impairs tonic autonomic regulation while sparing oscillatory cardiovascular rhythms in healthy humans
    Ferrettia, Guido
    Iellamo, Ferdinando
    Pizzinelli, Paolo
    Kenfack, Marcel A.
    Lador, Frederic
    Lucini, Daniela
    Porta, Alberto
    Narkiewicz, Krzysztof
    Pagani, Massimo
    [J]. JOURNAL OF HYPERTENSION, 2009, 27 (03) : 551 - 561
  • [24] FRIMAN G, 1979, ACTA MED SCAND, V205, P389
  • [25] WORK CAPACITY DURING 30 DAYS OF BED REST WITH ISOTONIC AND ISOKINETIC EXERCISE TRAINING
    GREENLEAF, JE
    BERNAUER, EM
    ERTL, AC
    TROWBRIDGE, TS
    WADE, CE
    [J]. JOURNAL OF APPLIED PHYSIOLOGY, 1989, 67 (05) : 1820 - 1826
  • [26] Plasticity of skeletal muscle mitochondria:: Structure and function
    Hoppeler, H
    Flück, M
    [J]. MEDICINE AND SCIENCE IN SPORTS AND EXERCISE, 2003, 35 (01) : 95 - 104
  • [27] Non-invasive cardiac output assessment during moderate exercise:: pulse contour compared with CO2 rebreathing
    Houtman, S
    Oeseburg, B
    Hopman, MTE
    [J]. CLINICAL PHYSIOLOGY, 1999, 19 (03): : 230 - 237
  • [28] Performing at extreme altitude: muscle cellular and subcellular adaptations
    Howald, H
    Hoppeler, H
    [J]. EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY, 2003, 90 (3-4) : 360 - 364
  • [29] Haematocrit, plasma volume and noradrenaline in humans during simulated weightlessness for 42 days
    Johansen, LB
    Gharib, C
    Allevard, AM
    Sigaudo, D
    Christensen, NJ
    Drummer, C
    Norsk, P
    [J]. CLINICAL PHYSIOLOGY, 1997, 17 (02): : 203 - 210
  • [30] KASHIHARA H, 1994, ACTA PHYSIOL SCAND, V150, P19