New York, Oct 26 (IANS): Yoga offers a promising approach to fight spinal stiffness and reduced mobility that astronauts on long missions in space suffer from, say researchers.

Space travel may lead to atrophy of the muscles supporting the spine -- which do not return to normal even several weeks after their return to the Earth, the study found.

The results provide new insights into the elevated rates of back pain and spinal disc disease associated with prolonged spaceflight, said one of the researchers, Douglas Chang of the University of California - San Diego. 

The finding of muscle atrophy suggests possible preventive steps to reduce the spinal effects of spaceflight, according to the researchers.

For instance, core-strengthening exercises, like those recommended for patients with back pain on Earth, might be a useful addition to the astronaut exercise training programme.

Yoga might be another promising approach, especially for addressing spinal stiffness and reduced mobility, the researchers pointed out.

For the study, six NASA crew members were studied before and after spending four to seven months in "microgravity" conditions on the International Space Station. 

Each astronaut underwent magnetic resonance imaging (MRI) scans of the spine before their mission, immediately after their return to the Earth, and again one to two months later.

The goal was to understand factors affecting lumbar spine strength and low back pain during long-duration spaceflight, as well as the spine's response after returning to the Earth gravity.

The MRI scans indicated significant atrophy of the paraspinal lean muscle mass -- which plays a critical role in spinal support and movement -- during the astronauts' time in space, said the study published in the journal Spine.