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The Elucidation of the Re-adaptation on the Attitude Control after Return from Long- term Space Flight (Synergy)
Principal Investigator
Research Area:
Muscle physiology
Radiation Effects Team
Species Studied
Scientific Name: Homo sapiens Species: Human

Astronauts returning from a long stay in space will be observed to learn more about the adaptive processes in the somatosensory system and the lower limb skeletal muscle and acquire data that could contribute to astronaut rehabilitation after returning from space. To accomplish the above objective, astronauts who have stayed for a long time in space will be studied to measure the following items before and after their stay in orbit:
(1) Comparison of muscle activation patterns in lower limb antagonistic muscles
(2) Blood flow measurement in the lower limb skeletal muscle
(3) Body sway balance measurement.

In the present study, based on the hypothesis that the factors that make it difficult for astronauts to walk immediately after their return from orbit and before re-adaptation to the ground are the unevenness in the state of the lower limb antagonistic muscles, which adapted to the long-term space stay, and the somatosensory regulation in the vestibular system and cerebellum, investigators aim to study astronauts who have stayed in space for a long time, observing them to learn about the process, including (1) co-contraction of the lower limb antagonist muscles, (2) lower limb skeletal muscle blood flow, and (3) center of gravity regulated by the somatosensory system are re-adapted to land, and acquire basic data regarding the re-adaptation process immediately after return.

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Musculoskeletal physiology
Blood flow velocity

Data Information
Data Availability
Archiving in progress. Data is not yet available for this experiment.

Blood flow
Body sway
Video imaging

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Expedition 41 09/10/2014 11/09/2014 29 days
Expedition 42 11/10/2014 03/11/2015 121 days
Expedition 43 03/11/2015 06/10/2015 91 days
Expedition 44 06/10/2015 09/11/2015 93 days
Expedition 45 09/11/2015 12/11/2015 91 days
Expedition 46 12/11/2015 03/02/2016 82 days
Expedition 47 03/02/2016 06/18/2016 108 days
Expedition 48 06/18/2016 09/06/2016 80 days
Expedition 49 09/06/2016 10/30/2016 54 days

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Pamela A. Bieri
Institutional Support
Japan Aerospace Exploration Agency (JAXA)