Space

August 24, 2012

NASA study provides new findings on protecting astronauts’ bones through diet, exercise

Eating the right diet and exercising hard in space helps protect International Space Station astronauts’ bones, a finding that may help solve one of the key problems facing future explorers heading beyond low Earth orbit.

A new study, published this month in the Journal of Bone and Mineral Research, evaluated the mineral density of specific bones as well as the entire skeleton of astronauts who used the Advanced Resistive Exercise Device, a 2008 addition to the space station that can produce resistance of as much as 600 pounds in microgravity. Resistance exercise allows astronauts to “lift weights” in weightlessness.

Researchers compared data measured from 2006 until the new device arrived, when astronauts used an interim workout that offered about half the total resistance of the ARED. The researchers found astronauts using the advanced exercise system returned to Earth with more lean muscle and less fat, and maintained their whole body and regional bone mineral density compared to when they launched. Crew members using ARED also consumed sufficient calories and vitamin D, among other nutrients. These factors are known to support bone health and likely played a contributing role.

“After 51 years of human spaceflight, these data mark the first significant progress in protecting bone through diet and exercise,” said Scott M. Smith, NASA nutritionist at the agency’s Johnson Space Center in Houston and lead author of the publication.

Since the 1990s, resistance exercise has been thought to be a key method of protecting astronauts’ bones. Normal, healthy bone constantly breaks down and renews itself, a process called remodeling. As long as these processes are in balance, bone mass and density stay the same. Earlier studies of Russian Mir space station residents found an increased rate of breakdown, but little change in the rate of regrowth that resulted in an overall loss in bone density. In the new study, researchers looked at preflight and postflight images of bone using X-ray densitometry, as well as in-flight blood and urine measurements of chemicals that reflect bone metabolism. In crew members who used the ARED device during spaceflight, bone breakdown still increased, but bone formation also tended to increase, likely resulting in the maintenance of whole bone mineral density.

“The increase in both bone breakdown and formation suggests that the bone is being remodeled, but a key question remains as to whether this remodeled bone is as strong as the bone before flight,” said Dr. Jean Sibonga, bone discipline lead at Johnson and coauthor of the study.

Studies to evaluate bone strength before and after flight are currently under way.

Beyond bone strength, further study is required to determine the best possible combination of exercise and diet for long-duration crews. Dietary effects on bone are being studied on the space station right now, with one experiment evaluating different ratios of animal protein and potassium in the diet on bone health. Another is looking at the benefits for bone of lowering sodium intake.

 




All of this week's top headlines to your email every Friday.


 
 

 

Boeing concludes commercial crew space act agreement for CST-100/Atlas V

Boeing has successfully completed the final milestone of its Commercial Crew Integrated Capability Space Act Agreement with NASA. The work and testing completed under the agreement resulted in significant maturation of Boeing’s crew transportation system, including the CST-100 spacecraft and Atlas V rocket. NASA in July approved the Critical Design Review Board milestone for Boeing’...
 
 

NASA partners with leading technology innovators to enable future exploration

Recognizing that technology drives exploration, NASA has selected four teams of agency technologists for participation in the Early Career Initiative pilot program. The program encourages creativity and innovation among early career NASA technologists by engaging them in hands-on technology development opportunities needed for future missions. NASA’s Space Technology Mission Directorate c...
 
 

New commercial rocket descent data may help NASA with future Mars landings

NASA successfully captured thermal images of a SpaceX Falcon 9 rocket on its descent after it launched in September from Cape Canaveral Air Force Station, Fla. The data from these thermal images may provide critical engineering information for future missions to the surface of Mars. “Because the technologies required to land large payloads on Mars...
 

 
Image courtesy of NASA, J. Lotz, (STScI

NASA’s Hubble finds extremely distant galaxy through cosmic magnifying glass

Image courtesy of NASA, J. Lotz, (STScI The mammoth galaxy cluster Abell 2744 is so massive that its powerful gravity bends the light from galaxies far behind it, making these otherwise unseen background objects appear larger a...
 
 
NASA photograph

NASA TV to air Russian spacewalk from International Space Station

NASA photograph Expedition 41 Commander Max Suraev and Flight Engineer Alexander Samokutyaev of the Russian Federal Space Agency will don Orlan spacesuits and step outside the International Space Station Oct. 22, to perform wor...
 
 
Ball Aerospace photograph

Ball Aerospace green propellant infusion mission to host three DOD space experiments

Ball Aerospace photograph The NASA and Ball Aerospace & Technologies Corp. Green Propellant Infusion Mission (GPIM) will fly three Defense Department experimental hosted payloads when it launches in 2016. The NASA and Ball ...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>