This campaign introduced the multi-discipline approach to understanding the physiological effects on humans exposed to a microgravity environment. The bed rest model was selected as the ground-based analog to space flight to simulate the effects of microgravity. As part of this multi-discipline approach, test protocols were selected as a means to compare spaceflight and bed rest responses. Together, these tests were called the Standard Measures and were collected on the three subjects from Campaign 1.
The results from these assessments became part of the medical monitoring of the subjects, increased the description of the physiologic responses to bed rest in humans, provided a basis to compare bed rest results with results from flight investigations, served as control data for the countermeasures and provided ancillary data to individual investigators. These tests reflect the same tests as those performed on ISS astronauts as part of their medical evaluation. Additional testing was performed to assess different physiological systems and their response to bed rest.
In addition, two external principal investigations were included with the Campaign 1 science requirements:
Campaign 1 represented the first in a series of investigations to study the effects of microgravity in a ground-based model using the multi-discipline approach. Overall, Campaign 1 proceeded very smoothly with only minor technical issues that were quickly resolved. Based on the preliminary results from Campaign 1, the physiological changes shown by the subjects participating in this study were similar to the changes observed in human exposed to space flight. A number of lessons learned from Campaign 1 have been identified and have been incorporated into subsequent campaigns. The bed rest design employed during this campaign appears to provide an excellent ground-based model to study the varied physiological changes. The data collected from the three subjects in this campaign will be combined with additional subjects and serve as control data for the evaluation and assessment of potential countermeasures. Subsequent campaigns have been extended to 90 days of head-down tilt bed rest, which should enhance the physiological changes and allow for a more complete comparison with flight results and countermeasure evaluations.