[Postural adjustments associated with voluntary mobilization of the arm in microgravity conditions].

Adaptation of posture and of postural adjustments involved in voluntary elevation of the arm was studied during a seven day spaceflight. Results show an important forward inclination of the body at beginning of the flight. After three days in flight the position of the body was similar to the terrestrial posture. Together with this inclination, a redistribution of the electromyographic activities between flexor and extensor muscles of the ankle was observed. Anticipatory postural adjustments were always present in microgravity. These results are interpreted on the basis of body scheme.