The underwater environment: cardiopulmonary, thermal, and energetic demands.

@article{Pendergast2009TheUE,
  title={The underwater environment: cardiopulmonary, thermal, and energetic demands.},
  author={David R. Pendergast and Claes E. G. Lundgren},
  journal={Journal of applied physiology},
  year={2009},
  volume={106 1},
  pages={
          276-83
        }
}
Water covers over 75% of the earth, has a wide variety of depths and temperatures, and holds a great deal of the earth's resources. The challenges of the underwater environment are underappreciated and more short term compared with those of space travel. Immersion in water alters the cardio-endocrine-renal axis as there is an immediate translocation of blood to the heart and a slower autotransfusion of fluid from the cells to the vascular compartment. Both of these changes result in an increase… 
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