Exercise induced plasma volume expansion is accompanied by a decrease in intracellular fluid volume

To test the hypothesis that exercise-induced hypervolemia is a posture-dependent process, we measured plasma volume, plasma albumin content, and renal function in seven healthy subjects for 22 h after single upright (Up) or supine (Sup) intense (85% peak oxygen consumption rate) exercise. This posture was maintained for 5 h after exercise. Plasma volume decreased during exercise but returned to control levels by 5 h of recovery in both postures. By 22 h of recovery, plasma volume increased 2.4 ± 0.8 ml/kg in Up but decreased 2.1 ± 0.8 ml/kg in Sup. The plasma volume expansion in Up was accompanied by an increase in plasma albumin content (0.11 ± 0.04 g/kg; P < 0.05). Plasma albumin content was unchanged in Sup. Urine volume and sodium clearance were lower in Up than Sup ( P < 0.05) by 5 h of recovery. These data suggest that increased plasma albumin content contributes to the acute phase of exercise-induced hypervolemia. More importantly, the mechanism by which exercise influences the distribution of albumin between extra- and intravascular stores after exercise is altered by posture and is unknown. We speculate that factors associated with postural changes (e.g., central venous pressure) modify the increase in plasma albumin content and the plasma volume expansion after exercise.

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HORMONAL REGULATION OF THE EXERCISE INDUCED PLASMA VOLUME EXPANSION

Medicine & Science in Sports & Exercise ◽

10.1097/00005768-200205001-00637 ◽

2002 ◽

Vol 34 (5) ◽

pp. S113

Author(s):

W Schmidt ◽

G deGraet ◽

D Boening

Keyword(s):

Plasma Volume ◽

Hormonal Regulation ◽

Volume Expansion ◽

Plasma Volume Expansion ◽

Exercise Induced

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Exercise-induced plasma volume expansion and post-exercise parasympathetic reactivation

European Journal of Applied Physiology ◽

10.1007/s00421-008-0925-1 ◽

2008 ◽

Vol 105 (3) ◽

pp. 471-481 ◽

Cited By ~ 55

Author(s):

M. Buchheit ◽

P. B. Laursen ◽

H. Al Haddad ◽

S. Ahmaidi

Keyword(s):

Plasma Volume ◽

Volume Expansion ◽

Plasma Volume Expansion ◽

Post Exercise ◽

Parasympathetic Reactivation ◽

Exercise Induced

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Operation Everest III: role of plasma volume expansion onV˙o2 max during prolonged high-altitude exposure

Journal of Applied Physiology ◽

10.1152/jappl.2000.89.1.29 ◽

2000 ◽

Vol 89 (1) ◽

pp. 29-37 ◽

Cited By ~ 47

Author(s):

Paul Robach ◽

Michèle Déchaux ◽

Sébastien Jarrot ◽

Jenny Vaysse ◽

Jean-Christophe Schneider ◽

...

Keyword(s):

High Altitude ◽

Plasma Volume ◽

Volume Expansion ◽

Plasma Renin ◽

Plasma Volume Expansion ◽

Exercise Induced ◽

Male Subjects ◽

Increased Activity ◽

Volume Decrease

We hypothesize that plasma volume decrease (ΔPV) induced by high-altitude (HA) exposure and intense exercise is involved in the limitation of maximal O2 uptake (V˙o2 max) at HA. Eight male subjects were decompressed for 31 days in a hypobaric chamber to the barometric equivalent of Mt. Everest (8,848 m). Maximal exercise was performed with and without plasma volume expansion (PVX, 219–292 ml) during exercise, at sea level (SL), at HA (370 mmHg, equivalent to 6,000 m after 10–12 days) and after return to SL (RSL, 1–3 days). Plasma volume (PV) was determined at rest at SL, HA, and RSL by Evans blue dilution. PV was decreased by 26% ( P < 0.01) at HA and was 10% higher at RSL than at SL. Exercise-induced ΔPV was reduced both by PVX and HA ( P < 0.05). Compared with SL, V˙o2 max was decreased by 58 and 11% at HA and RSL, respectively.V˙o2 max was enhanced by PVX at HA (+9%, P < 0.05) but not at SL or RSL. The more PV was decreased at HA, the moreV˙o2 max was improved by PVX ( P < 0.05). At exhaustion, plasma renin and aldosterone were not modified at HA compared with SL but were higher at RSL, whereas plasma atrial natriuretic factor was lower at HA. The present results suggest that PV contributes to the limitation ofV˙o2 max during acclimatization to HA. RSL-induced PVX, which may be due to increased activity of the renin-aldosterone system, could also influence the recovery ofV˙o2 max.

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Increased renal tubular sodium reabsorption during exercise-induced hypervolemia in humans

Journal of Applied Physiology ◽

10.1152/jappl.2001.91.3.1229 ◽

2001 ◽

Vol 91 (3) ◽

pp. 1229-1236 ◽

Cited By ~ 27

Author(s):

Kei Nagashima ◽

Jauchia Wu ◽

Stavros A. Kavouras ◽

Gary W. Mack

Keyword(s):

Blood Flow ◽

Renal Blood Flow ◽

Plasma Volume ◽

Volume Expansion ◽

Tubular Reabsorption ◽

Proximal Tubules ◽

Plasma Volume Expansion ◽

Saline Loading ◽

Exercise Induced ◽

Renal Tubular

We tested the hypothesis that renal tubular Na+ reabsorption increased during the first 24 h of exercise-induced plasma volume expansion. Renal function was assessed 1 day after no-exercise control (C) or intermittent cycle ergometer exercise (Ex, 85% of peak O2 uptake) for 2 h before and 3 h after saline loading (12.5 ml/kg over 30 min) in seven subjects. Ex reduced renal blood flow ( p-aminohippurate clearance) compared with C (0.83 ± 0.12 vs. 1.49 ± 0.24 l/min, P < 0.05) but did not influence glomerular filtration rates (97 ± 10 ml/min, inulin clearance). Fractional tubular reabsorption of Na+ in the proximal tubules was higher in Ex than in C ( P < 0.05). Saline loading decreased fractional tubular reabsorption of Na+ from 99.1 ± 0.1 to 98.7 ± 0.1% ( P < 0.05) in C but not in Ex (99.3 ± 0.1 to 99.4 ± 0.1%). Saline loading reduced plasma renin activity and plasma arginine vasopressin levels in C and Ex, although the magnitude of decrease was greater in C ( P < 0.05). These results indicate that, during the acute phase of exercise-induced plasma volume expansion, increased tubular Na+ reabsorption is directed primarily to the proximal tubules and is associated with a decrease in renal blood flow. In addition, saline infusion caused a smaller reduction in fluid-regulating hormones in Ex. The attenuated volume-regulatory response acts to preserve distal tubular Na+ reabsorption during saline infusion 24 h after exercise.

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