Previously, there has been little interaction between those studying the effects of gravity on plants, animals and cells, he said. By bringing the group together, they hoped to stimulate the scientific community to use the unique facilities of the space station, he said. When astronauts are weightless for more than a short time, bones lose calcium, muscles wither, and blood moves from the legs to the face and head, said Fuller. The heart becomes weaker, because it has less resistance to push against. There are also changes in circadian rhythms, temperature regulation and body composition.
Scientists study the effects of gravity on the body using centrifuges.
In a typical experiment, the centrifuge is used to increase gravitational force to double normal gravity, or 2g, he said. By looking at the effects of gravity in a range from 1 g to 2 g, scientists could estimate the effects of gravitational forces outside this range, said Fuller. Recent research in humans and animals shows that changes in gravity cause shifts in metabolism, said Fuller. Space shuttle astronauts chose less fatty meals, but did not lose body fat. Research in Fuller's laboratory has shown that metabolic shifts are triggered by the effects of gravity on the inner ear.