NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Flexor bias of joint position in humans during spaceflightThe ability to estimate ankle and elbow joint position was tested before, during, and after a 17-day spaceflight. Subjects estimated targeted joint angles during isovelocity (IsoV) joint movements with agonist muscle groups either active or relaxed. These movements included elbow extension (EE) and elbow flexion (EF), and plantarflexion (PF) and dorsiflexion (DF) of the ankle. Subjects also estimated these joint positions while moving the dynamometer at their chosen (variable) velocity (VarV) during EE and PF. For IsoV tests, no differences were observed between active and passive movements for either the ankle or elbow. Compared with those of pre-flight test days, estimates of targeted elbow joint angles were approximately 5 degrees to 15 degrees more flexed in-flight, and returned toward the pre-flight values during recovery. The spaceflight effects for the ankle were inconsistent and less prevalent than those for the elbow. The VarV PF test condition for the 120 degrees target angle at the ankle exhibited approximately 5 degrees to 7 degrees more DF target angle estimates in-flight compared with those pre- or post-flight. In contrast, during IsoV PF there was a tendency for ankle estimates to be approximately 2 degrees to 3 degrees more PF after 2-3 days exposure to spaceflight. These data indicate that during spaceflight the perception of elbow extension is greater than actuality, and are consistent with the interpretation that microgravity induced a flexor bias in the estimation of the actual elbow joint position. Moreover, these effects in joint proprioception during spaceflight were observed in individual isolated single-joint movements during tasks in which vestibular function in maintaining posture were minimal.
Document ID
20040087608
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
McCall, G. E.
(University of California 621 Circle Drive South, 2301 Life Science, Los Angeles, CA 90095, United States)
Goulet, C.
Boorman, G. I.
Roy, R. R.
Edgerton, V. R.
Date Acquired
August 21, 2013
Publication Date
September 1, 2003
Publication Information
Publication: Experimental brain research. Experimentelle Hirnforschung. Experimentation cerebrale
Volume: 152
Issue: 1
ISSN: 0014-4819
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: DE07212
Distribution Limits
Public
Copyright
Other
Keywords
STS-78 Shuttle Project
manned
short duration
NASA Experiment Number 284036
Flight Experiment
NASA Discipline Musculoskeletal
NASA Program Biomedical Research and Countermeasures
Non-NASA Center

Available Downloads

There are no available downloads for this record.
No Preview Available