Mechanism for the posture-specific plasma volume increase after a single intense exercise protocol

• Published in: Journal of applied physiology (1985) Vol. 86; no. 3; pp. 867 - 873
• Main Authors: Nagashima, Kei, Mack, Gary W, Haskell, Andrew, Nishiyasu, Takeshi, Nadel, Ethan R
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.03.1999; American Physiological Society
• Subjects: Adult; Anatomy & physiology; Biological and medical sciences; Blood; Blood Pressure - physiology; Blood Proteins - metabolism; Creatinine - urine; Electrolytes - urine; Exercise; Exercise - physiology; Female; Fundamental and applied biological sciences. Psychology; Heart Rate - physiology; Hematocrit; Hormones - blood; Humans; Kidney Function Tests; Male; Oxygen Consumption - physiology; Plasma; Plasma Volume - physiology; Posture; Posture - physiology; Space life sciences; Supine Position - physiology; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Physical exercise; Human; Renal function; Blood volume; Bicycle ergometer; Hypervolemia; Albumin; Plasma volume; Posture; NASA Discipline Cardiopulmonary; Non-NASA Center
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1999.86.3.867

The John B. Pierce Laboratory and Departments of Cellular and Molecular Physiology and of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut 06519 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. exercise-induced hypervolemia; blood volume; plasma albumin  Deceased December 1998.