Zero gravity: Research shows astronauts lose 2 per cent of their bone mass a month. [File photo]
Last Update: Saturday, October 7, 2006. 12:00pm (AEST)

Vibrations may keep astronauts' bones healthy

A new technology, which sends signals that make bones react as though they are being exercised, is being tested on astronauts.

An article published in the Journal of Bone and Mineral Research found that crew members on the International Space Station lost up to 2 per cent of bone mass per month because gravity was not acting on their bodies.

The new technology's co-inventor, Professor Clinton Rubin of the State University of New York, says being in space accelerates the ageing process.

"Think of an astronaut that's basically being deprived of weight bearing, or deprived of gravity, as a model for ageing," he said.

"As we age, we're less and less active, and without the proper mechanical signals to the skeleton, our skeleton begins to waste away.

"Put yourself up in space, where essentially you're in a vacuum of mechanical signals, you're just not loading your skeleton at all.

"In essence, it's a means of accelerated ageing."

Professor Rubin says the goal of his research is to arrest that ageing process.

He says the technology works by vibrating astronauts' bones.

"The technology is based on putting very, very small mechanical signals into the skeleton, the same sort of things that their muscle would do when they're active," he said.

"The astronauts, when using the device for 10 minutes per day, would basically be harnessed to it ... with a very, very subtle spring.

"They'd sit there and they'd work on their laptop, or read a book while their skeleton is being stimulated."

Mars mission

Professor Rubin says the technology may help eliminate on the human-related factors that is stopping mankind from making the trip to Mars, which would take several years..

"Once they're [in space] for greater than 90 days or up to six months … they're putting their skeletons at a higher level of risk or fracture," he said.

"The challenge that you've got when you're thinking about a three-year round trip to Mars, is that what happens if you're losing 2 per cent of your bone per month.

"If you happen to trip and break your femur, or your thighbone while you're up on Mars, that it's quite a long way to the nearest hospital."