HOUSTON – (June 24, 2003) – Astronauts on extended missions go into space
with a spring in their step but rarely return from the International Space
Station (ISS) walking steady.

“We want to develop a training device to counter the effects while in space
and help astronauts recover more quickly upon return to Earth,” said Dr.
Jacob Bloomberg, a researcher on the National Space Biomedical Research
Institute’s (NSBRI) neurovestibular adaptation team.

Returning astronauts walk with an unstable gait and wide stance and can take
almost two weeks to fully recover their footing after a long-duration flight
on the ISS. A new treadmill training system being researched could help
shorten or remove post-flight balance problems and eventually help elderly
patients and others with similar problems.

Bloomberg and his team are using a new, integrated research protocol to
discover and test ways to counter the ill effects of space flight on the
balance and walking systems. The goal of the research is to develop an
in-flight treadmill training system that will improve the brain’s ability to
readapt to gravity environments whether it is a return to Earth or a landing
on Mars. In addition to developing training programs, Bloomberg is working
on better ways to evaluate balance and walking function in returning

“Rather than study individual systems in isolation we’re looking at how
multiple systems interact and adapt during space flight to cause balance
problems,” said Bloomberg, senior research scientist at NASA’s Johnson Space
Center. “We are working to understand how multiple, interdependent
full-body sensory-motor systems are integrated to produce a complex behavior
like walking.”

A person’s performance on a unique series of integrated tests – an obstacle
course, a treadmill and visual acuity test – will help the researchers
develop solutions to not only balance and mobility, but also eye
coordination. These tests will serve to evaluate the effectiveness of
in-flight interventions designed to reduce the negative effects of space
flight on post-flight balance and walking function.

During testing, subjects walk on a treadmill while head, eye and body
movements are recorded with a video-based motion capture system. At the
same time, other sensors record body accelerations and the vertical forces
that occur during each foot-fall; all this while subjects identify symbols
on a computer screen to measure visual acuity. With this unique set-up,
Bloomberg and his group can determine how the nervous system responds and
adapts to different alterations in sensory input during walking. To
complement the treadmill test, the obstacle course serves to help understand
the practical implications of sensory-motor changes that lead to post-flight
walking disturbances.

“This work will motivate the next generation of treadmill devices used on
the International Space Station. While astronauts are training to maintain
aerobic capacity and muscle strength, they will also be training their
brains to readapt to a gravity environment,” Bloomberg said. “Everyone is
told they need to exercise to maintain their heart and muscles, but rarely
do people train to keep their balance system in shape.”

Further development of these testing protocols will not only help develop
better tools to diagnose problems for elderly patients and others with
balance problems, but may also help train them to overcome these problems.


The NSBRI, funded by NASA, is a consortium of institutions studying the
health risks related to long-duration space flight. The Institute’s
research and education projects take place at more than 70 institutions
across the United States.