Cardiologists at Penn State's Milton S. Hershey Medical Center are putting people to bed for two weeks to learn more about how long-term bed rest affects the cardiovascular system.
They hope that the information will provide insights into how spaceflight and the lack of gravity affects astronauts.
In the study, funded by the National Aeronautics and Space Administration, 45 volunteers--20- to 40-year-old men--are being confined to bed for two weeks to mimic the conditions of weightlessness.
Cardiologist Lawrence Sinoway, professor of medicine, says astronauts may have difficulty standing after they return to Earth. They do not sleep well, and some develop muscle atrophy, reducing their ability to exercise.