Tuesday, May 19, 2009

Sit, Stand, Sit, Stand

Tight Tight Tight!

At 6:45 this morning, I pulled on my new Jobst compression stockings. I know the in the previous study, many subjects wore thigh-high compressors... but in this new campaign, we have slightly looser ones which reach just-below-the-knee.

These stockings are used to mimic the effect of lunar gravity on the blood in the legs. They are not painful or uncomfortable -- in fact I imagine I have it easier than Candace or Kevin, who had the thigh-highs in 2008. However, sometimes my toes get tingly, and I'm betting by the end of the day they may be numb!

NASA Lunar Study Lower mattress and upper mattress

At 7:30am, the lower mattress was removed from the bed, creating a large space. I knew about this part, since I watched them change the bed many times when "Melissa" was here. It's a standard hospital bed, but also note the rails underneath. You can clearly see part of the lower bed is missing; the remaining portion is designed to slide back and forth.

NASA Lunar Study The gap makes my sweats look like bell-bottoms ;)

Nurse Tammy tilted the bed to 9.5 degrees upward, at which point the upper mattress slid down partway, and caused me to plant my feet on the forceplate. This piece of hardware measures the load between my feet and the supporting surface, thus providing measurements of forces that the feet experience... and the data is communicated to a laptop in a rack attached to the side of the bed.

NASA Lunar StudyMy view of the forceplate

You can see from the pictures above, I can easily turn to the side (which is better for when I'm eating), but most of the time, I remain straight. This is what simulates the "lunar gravity" ... and is significantly easier to bear than micro-gravity! Which is to say, I've been in the tilted bed over 8 hours now, and have only had a mild backache. Last year, after 8 hours at a -6 degree tilt, I was feeling FAR more physiological changes. Makes sense! And it started me thinking: ANY amount of gravity is good! :) Certainly different from Earth gravity, but even a little force makes a difference.

NASA Lunar StudyMy view when "sitting" at the 9.5 degree tilt

After certain portions of time, the schedule calls for a bed reconfiguration. The force plate is removed, and a small stool is placed in the empty space. I slide down even more, and can "sit" on the stool until it's time to stand again. These phases are all designed to mimic lunar activites in modules, moonwalks, rover rides, and so on.

They had to make a few modifications for my stint in the bed, since at 5'1" I am the shortest person to do this study so far!