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Comparison of the Muscle Atrophy Research and Exercise System (MARES) and the HUMAC Norm Isokinetic Dynamometer (EORS_MARES)
Principal Investigator
Research Area:
Muscle physiology
Species Studied
Scientific Name: Homo sapiens Species: Human

Astronauts and cosmonauts lose muscle strength following long stays onboard the International Space Station (ISS). The Exercise Physiology Laboratory (EXL) at NASA-Johnson Space Center is responsible for assessing muscle strength in crewmembers in order to evaluate the effectiveness of exercise countermeasures performed during space flight as well as to track the success of their rehabilitation after landing. Currently, muscle strength assessment is carried out before and after space flight using a HUMAC NORM isokinetic dynamometer. The European Space Agency (ESA) has developed an isokinetic dynamometer (MARES) that will fly onboard the ISS. The purpose of this study was to compare the two isokinetic dynamometers by performing the same tests on each system to learn whether or not there is adequate agreement between them. In this project, the strength of muscles at the knee were tested.

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English KL, Hackney KJ, De Witt JK, Ploutz-Snyder RL, Goetchius EL, and Ploutz-Snyder LL. A ground-based comparison of the Muscle Atrophy Research and Exercise System (MARES) and a commercially available isokinetic dynamometer. Acta Astronautica. 2013. November; 92(1):3-9.

Exercise test

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Data Information
Data Availability
Archive is complete. Data sets are not publicly available but can be requested.
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Body weight
Concentric knee extension
Concentric knee flexion
Concentric muscle contractions
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Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
ECP 02/01/2005 12/31/2010 In Progress

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)