Skip to page content Mission Information


Integrated Resistance and Aerobic Exercise Training With Small Compact Exercise Equipment (BEDREST_iRATS)
Principal Investigator
Research Area:
Exercise physiology
Muscle physiology
Species Studied
Scientific Name: Homo sapiens Species: Human



Campaign 11 utilized 70 days of six degrees head-down bed rest. This study consisted of 13 days of pre bed rest for the non-exercise group and 21 days of pre bed rest for the exercise group, as well as 14 days of post bed rest. Head-down tilt bed rest relieves longitudinal gravitational loading of the cardiovascular, bone, and muscle systems. Healthy subjects exposed to prolonged bed rest experience some of the adaptive physiological responses and associated deconditioning seen in astronauts exposed to prolonged weightlessness. Campaign 11 onsisted of the integration of standard measures and visual monitoring with investigator study protocols. The objective of the Integrated Resistance and Aerobic Training (iRATS) was for subjects to perform six days per week of exercise training that consisted of a combination of high intensity resistance and aerobic exercise in order to maintain cardiovascular fitness and muscular strength and function during bed rest.

++ -- View more

Ploutz-Snyder LL, Downs M, Ryder J, Hackney K, Scott J, Buxton R, Goetchius E, and Crowell B. Integrated resistance and aerobic exercise protects fitness during bed rest. Medicne and Science in Sports and Exercise. 2014. February; 46(2):358-68. []

Ploutz-Snyder LL, Downs M, Goetchius E, Crowell B, English KL, Ploutz-Snyder R, Ryder JW, Dillon EL, Sheffield-Moore M, and Scott JM. Exercise training mitigates multi-system deconditioning during bed rest. Medicine and Science in Sports and Exercise. 2018 September; 50(9):1920-8. [DOI]

Magnetic resonance imaging (MRI)
Musculoskeletal physiology
Oxygen consumption

Photo Gallery
+ View digital images

Data Information
Data Availability
Archive is complete. Data sets are not publicly available but can be requested.
Data Sets+ Request data

Actin filament density
Cross Sectional Area leg
Fiber ATPase
Fiber cross bridge stiffness
Fiber enzymes
++ -- View more

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Campaign 11 05/11/2011 12/15/2014 3 years, 7 months, 4 days
iRATS14 11/09/2010 04/27/2011 160 days

Human Research Program (HRP) Human Research Roadmap (HRR) Information
Crew health and performance is critical to successful human exploration beyond low Earth orbit. The Human Research Program (HRP) investigates and mitigates the highest risks to human health and performance, providing essential countermeasures and technologies for human space exploration. Risks include physiological and performance effects from hazards such as radiation, altered gravity, and hostile environments, as well as unique challenges in medical support, human factors, and behavioral health support. The HRP utilizes an Integrated Research Plan (IRP) to identify the approach and research activities planned to address these risks, which are assigned to specific Elements within the program. The Human Research Roadmap is the web-based tool for communicating the IRP content.

The Human Research Roadmap is located at:

+ Click here for information of how this experiment is contributing to the HRP's path for risk reduction.

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Jessica Keune
Institutional Support
National Aeronautics and Space Administration (NASA)
Alternate Experiment Name
Proposal Date
Proposal Source
2011 Crew Health NNJ11ZSA002NA