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Plasma volume and biochemical changes in athletes during bed rest chronic hyperhydration
Y G Zorbas1, V L Yarullin, S D Denogradov
1Kosmic Biology and Medicine Institute, Sophia, Bulgaria.
Acta Astronautica
|September 7, 2001
Summary
Daily fluid and salt supplements (FSS) can help endurance athletes maintain plasma volume and reduce biochemical changes during bed rest (BR). This study shows FSS mitigates negative effects of prolonged inactivity.
Area of Science:
- Exercise Physiology
- Biochemistry
- Sports Science
Background:
- Bed rest (BR) can induce significant physiological changes, including alterations in plasma volume and biochemical markers.
- Endurance-trained athletes may experience unique physiological responses to BR.
- Fluid and salt supplements (FSS) are proposed to counteract BR-induced deconditioning.
Purpose of the Study:
- To evaluate the effect of daily FSS on plasma volume (PV) and biochemical changes during a 30-day BR period in male athletes.
- To compare the physiological responses between supplemented and unsupplemented athletes undergoing BR.
- To assess the efficacy of FSS in attenuating BR-induced deconditioning.
Main Methods:
- Thirty male athletes (22-26 years) were divided into three groups: unsupplemented ambulatory controls (UACS), unsupplemented bed rested (UBRS), and supplemented bed rested (SBRS).
- The SBRS group received 26 ml/kg body weight water and 0.1 g/kg body weight sodium chloride daily during 30 days of BR.
- Measurements included plasma volume, protein, albumin, electrolytes (Na, Cl, K), osmolality, creatinine, glucose, hematocrit (Hct), and hemoglobin (Hb).
Main Results:
- SBRS group showed a significant increase in PV and decreases in plasma protein, albumin, Na, Cl, K, glucose, creatinine, osmolality, Hct, and Hb compared to UBRS (P < 0.01).
- UBRS group exhibited a significant decrease in PV and increases in plasma protein, albumin, Na, Cl, K, glucose, creatinine, osmolality, Hct, and Hb compared to SBRS and UACS (P < 0.01).
- UACS group showed no significant changes in measured parameters compared to baseline.
Conclusions:
- Daily intake of FSS can effectively attenuate plasma volume losses during bed rest in endurance-trained athletes.
- FSS helps mitigate significant biochemical alterations associated with prolonged inactivity in athletes.
- Supplementation with fluids and salt is a viable strategy to counteract deconditioning effects of bed rest.
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