NASA is recruiting participants for a bed rest study that simulates conditions astronauts might experience as they travel through space.  For 70 days, participants will remain on bed rest, tilted slightly with their head down and feet up.  A second group of participants will also be in bed for 70 days, but they will be placed on a cardiovascular and resistance training workout regimen.  This group will use specially designed equipment that allows them to remain in the lying down position.  Throughout the study, researchers will monitor bone, muscle, heart and circulatory systems, and nervous systems, as well as nutritional condition and ability to fight off infections.

The experiment will take place at the University of Texas Medical Branch in Galveston, Texas.  Subjects that are on bed rest only will spend 97 days at the facility and subjects that are also exercising will spend 105 days at the facility.  The first phase, called the ambulatory period will last 13 days for bed rest only and 21 days for bed rest and exercise.  During this time, participants will be free to move around the facility and participate in activities as normal.  The second phase, the bed rest period, will last 70 days.  During the final phase, the recovery period, participants will spend 14 days free to move around the facility.  The research officials will slowly reintroduce normal activities to participants so they do not do too much after having no functioning for 70 days.  There will also be prearranged reconditioning activities.

According to CBS News, participants in this study can earn up to $18,000.  They are paying $1,200 week for the study, which can last up to 15 weeks.  This study is meant to test the conditions that astronauts experience during space travel. Specifically, NASA hopes to assess the physical changes that occur on these missions and determine how much body function is required for a person to complete a specific task.  Researchers hope to make space travel safer and develop methods that allow astronauts to more easily physically acclimate to daily life following space exploration.

A study in the Journal of Exercise Physiology describes the physiological effects of bed rest.  Researchers identify lowered energy expenditure, changes in the cardiovascular system, diminished muscle strength, and decreased bone mass.  These adverse effects occurred independently of the disease or condition that has required bed rest.  Researchers recommend using bed rest sparingly.