Anticipatory postural adjustments in conditions of simulated reduced gravity. Gait Posture 2008 Nov;28(4):538-44
Date
05/16/2008Pubmed ID
18479924DOI
10.1016/j.gaitpost.2008.03.014Scopus ID
2-s2.0-52049091264 (requires institutional sign-in at Scopus site) 6 CitationsAbstract
The study investigates the role of decreased gravity on anticipatory postural adjustments (APAs). Subjects performed fast bilateral arm-raising movements and load releases while in conditions of normal and reduced gravity. Reduced gravity conditions were simulated by changing the ratio between the body weight and mass. Electromyographic (EMG) activity of dorsal and ventral trunk and leg muscles, as well as ground reaction forces, were recorded and quantified within the time intervals typical of APAs. Anticipatory postural adjustments were seen in normal gravity conditions as well as in simulated reduced gravity conditions. However, in decreased gravity conditions, the magnitudes of the anticipatory integrals of electromyography muscle activity (EMG) were smaller compared to normal gravity. Moreover, there was a linear relation between EMG and simulated decreased gravity and between the displacement of the center of pressure (COP) and simulated gravity. The study provides new data on the effect of gravity in feed-forward postural control and stresses the importance of taking into consideration its role in the control of upright posture.
Author List
Li X, Aruin ASAuthor
Xiaoyan Li PhD Assistant Professor in the Neurology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Adaptation, PhysiologicalAdult
Electromyography
Female
Humans
Leg
Male
Mechanoreceptors
Middle Aged
Muscle, Skeletal
Posture
Task Performance and Analysis
Weightlessness Simulation