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.


 
 

 

Headlines November 24, 2014

News: Hagel said to be stepping down as defense chief under pressure - Defense Secretary Chuck Hagel is stepping down under pressure, the first cabinet-level casualty of President Obama’s Democratic majority in the Senate and a beleaguered national security team that has struggled to stay ahead of an onslaught of global crises. Afghan mission for U.S....
 
 

News Briefs November 24, 2014

Fog forces five U.S. choppers to land in Polish field Officials say that that fog forced five U.S. Army helicopters to make an emergency landing in a Polish field and spend the night there, the second such incident since September. The U.S. Army said 15 soldiers were moving equipment to their base in Germany Nov....
 
 
Air Force photograph by Samuel King Jr.

Navy’s first F-35C squadron surpasses 1,000 flight hours

Air Force photograph by Samuel King Jr. An F-35C Lightning II aircraft piloted by Lt. Cmdr. Chris Tabert, assigned to Strike Fighter Squadron (VFA) 101, flies the squadron’s first local sortie. The F-35C is the carrier va...
 

 
boeing-SC-787

Boeing South Carolina begins final assembly of its first 787-9 Dreamliner

Boeing has started final assembly of the 787-9 Dreamliner at its South Carolina facility. The team began joining large fuselage sections of the newest 787 Nov. 22 on schedule, a proud milestone for the South Carolina team and a...
 
 
Lockheed Martin image

Ball Aerospace equips Orion mission with key avionics, antenna hardware

Lockheed Martin image Ball Aerospace & Technologies Corp. is providing the phased array antennas and flight test cameras to prime contractor Lockheed Martin for Orion’s Exploration Flight Test-1 (EFT-1), which is an u...
 
 

Salina, Kansas, recalls anniversary of shuttered base

It has been 50 years this month since the announcement that Schilling Air Force Base was closing rattled Salina residents. The Salina Journal, which carried news of the closure in its Nov. 19, 1964, editions, reported that the economic disaster then spared no part of the community – real estate, retail, civic involvement, church attendance,...
 




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>