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Ground Reaction Force and Joint Torque Comparison of the Advanced Resistive Exercise Device (ARED), Free Weights, and Smith Machine (EORS_GRF)
Principal Investigator
Research Area:
Exercise physiology
Species Studied
Scientific Name: Homo sapiens Species: Human

Currently, bedrest studies are designed to simulate long-duration space flight. During these studies, resistive exercise was incorporated as a countermeasure to the detrimental physiological effects of unweighting the body, including skeletal muscle atrophy and loss of bone mineral density. All exercise must be performed in a supine position.

NASA has initiated the design and construction of an Advanced Resistive Exercise Device (ARED) for the International Space Station. The primary resistive mechanism of ARED is a pair of large vacuum cylinders containing pistons and a series of levers that attach to a lift bar. Using this device for bed rest studies poses unique design and logistical challenges. However, there are currently free weight systems that can readily be employed for supine exercise. Therefore, it may be possible to allow subjects to exercise with free weights, and to interpret results to be similar to those that would occur if ARED were used. On the other hand, it may be vital that ARED is used as the resistive exercise device during the bedrest studies if the loads applied to the body are different than with free weights. It is important to understand the differences between the two exercise modes to better understand training adaptations that will result from their use.

The purpose of this evaluation was to compare the ground reaction forces and ankle, knee and hip joint torques generated by human subjects during squat and deadlift exercises between the ARED, free weights, and the Smith machine.

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Exercise test
Knee joint
Ankle joint
Hip joint

Photo Gallery
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Data Information
Data Availability
Archive is complete. No data sets are available for this experiment. Please Contact LSDA if you know of available data for this investigation.

Ankle torque
Ground reaction forces
Hip Torque
Joint torque
Knee torque
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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)
Alternate Experiment Name
GRF Comparison Study