Paper of the Month-(November 2018) from Dr. Edgell's research group

Edgell H, Grinberg A, Beavers KR, Gagné N,  Hughson RL. Efficacy of fluid loading as a countermeasure to the hemodynamic and hormonal changes of  28-h head-down bed rest. Physiol Rep. 2018 Sep;6(19):e13874. doi: 10.14814/phy2.13874.

Significance of the research:

This study investigated the effects of the standard NASA fluid-loading protocol on men who underwent 28hrs of head-down bed rest (which is a short-term Earth based model for space travel). NASA typically provides fluid-loading to astronauts 2 hours before their return to earth upon the assumption that it increases blood volume/blood pressure and will therefore help prevent them from fainting when they stand up on earth. However, using a bed-rest model and lower body negative pressure to mimic Earth's gravity when standing we found that the standard fluid-loading does not in fact increase blood volume/blood pressure due to compensatory changes in fluid regulatory hormones such as the renin-angiotensin-aldosterone pathway.

Click here to view a PDF document of this article.