May 24, 2011

NASA Astronauts Try Out New Spacewalk Preps

NASA said on Tuesday that astronauts will try a new set of exercises to prepare them for the change in pressure they encounter on their spacewalk outside the International Space Station.

The space agency said the "slow motion hokey pokey" exercises are designed to prevent decompression sickness known as the bends, which is similar to what scuba divers face if they rise to the surface too quickly.

Astronauts typically get their spacesuits on early and take a series of steps, like breathing pure oxygen through a mask, in order to help get rid of nitrogen in the body.

Too much nitrogen can form gas bubbles in their bodies as they strolled in space, causing pain in the joints, paralysis or death.

Astronauts used to camp out overnight in an airlock where the pressure was 10.2 pounds per square inch on the eve of spacewalks.

The new combination of breathing and low-effort exercises aims to skip the camp out but still gradually purge nitrogen from the bloodstream of the spacewalkers through extremely low impact exercise.

Lead spacewalk officer Allison Bollinger said on a perceived exertion scale of six to 20, where six "sitting there not doing anything, we are asking crew members to target seven,"

"This is equivalent to walking a mile in about 70 minutes, so this is very light exercise," she explained.

Bollinger showed reporters a video of astronauts in their spacesuits, kicking on leg from the knee down, followed by a long pause, then the other leg kicking, then another long pause.

"This is what we call the slow motion hokey-pokey," she said.

The astronauts will do a "50-minute resting prebreathe," and then break up that resting session into two separate parts for extra tests this time around.

"The one drawback to this protocol though is it does take longer in the morning to get out the door than it does with the campout protocol," said Bollinger. "About 30 minutes later."

The spacewalk will begin on Wednesday at 1:46 E.T. in the U.S.


Image Caption: Astronaut Drew Feustel works in the vacuum of space during the first of four spacewalks during the STS-134 mission of Space Shuttle Endeavour to the International Space Station. This was the 245th spacewalk conducted by U.S. astronauts and was Feustel's fourth spacewalk. Image Credit: NASA


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