Integrated physiological simulation of an astronaut exercise protocol

Although exercise has been used as a countermeasure to the de-conditioning effects of microgravity on manned space flights since the US Skylab missions, its use has hot yet produced post-flight values of bone density, muscle strength, and cardiorespiratory conditioning equal to pre-flight values. On the International Space Station, US astronauts spend roughly 2.5 hours per day performing exercise and setting up / tearing down exercise equipment, significantly reducing the time available for mission-related activities. The National Space Biomedical Research Institute convened an Exercise Workshop in 2002 that affirmed the value of producing a simulation of exercise to study the effects of exercise protocols. As an initial effort, in collaboration with researchers at the University of Washington, Case Western Reserve University, and the Massachusetts Institute of Technology, the Johns Hopkins University Applied Physics Laboratory developed a prototype integrated simulation of the 25-minute cycle ergometer exercise protocol used by US astronauts since Skylab. This includes simulations of cardiovascular system dynamics, tissue-bed blood flows, whole-body metabolism, and respiration. The High Level Architecture standard for simulation interoperability of the Institute of Electrical and Electronics Engineers is used to connect these components.