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'A possible way to reverse the head-ward fluid shift is to apply lower body negative pressure.'

'The Russian side of the space station includes a Chibis suit that was used to test this method. The suit basically acts as vacuum-sealed pants, according to the study authors.'

"It encompasses the lower limbs in a hard enclosure that is sealed at the waist and connected to a vacuum pump to decrease the pressure in the chamber around the lower limbs to subatmospheric pressure," the authors wrote. "Lower body negative pressure sequesters fluid volume, mainly venous blood, in the lower extremities and is used by cosmonauts on the ISS as a countermeasure for postflight orthostatic intolerance."

Perhaps I can provide a little enlightenment here, as I am acutely aware of what they're speaking of in the first hand, albeit in reverse. You are aware of the heart being essentially being a four-bellowed pump. Now, while our anatomy is optimized for this planet's gravity, the heart itself isn't powerful enough on it's own to move the volume of blood our cells, organs, and limbs all need simutaneously. Our venous system is governed by a series of valves of sorts, to prevent the backflow of blood and keep it moving forward in the network of vascular highways it constantly travels as the heart beats the blood in rhythm through at regular intervals. The fresh blood is used by our cells to 'breathe' and the lymphatic system generally acts as the waste transfer plumbing to move the blood from the veins into the arteries, where it is returned to the liver, spleen, and lungs for filtering and refreshing. If the blood is sequestered in the lower limbs, it can (and will) leak through the walls and pool in the interstitial tissues, causing edema, and can permit fluid to back up into the thoracic region, which can initiate congestive heart failure. I suffer from lymphedema, venous stasis, and venous stasis dermatitis (dead red cells rising upward to the surface layers of the skin, AKA, reverse bruising) due to a vicious attack on both my lower legs by stapth infections a few years back. I wear compression stockings on both legs to keep a positive blood flow back to my heart. Sort of a reverse Chibis suit - instead of drawing blood and fluid back down into my legs with a vacuum, I'm wringing it out of the tissues to keep it from pooling down there. Swollen calves and ankles are one thing; having it build up to the point where your skin blisters and leaks fluid down your leg like a sunburn is another. 14.7 PSI, zero G, different shades of gray. Or, you say po-tay-to, I say po-tah-to........