TY - JOUR
T1 - Coexistence of stability and mobility in postural control
T2 - Evidence from postural compensation for respiration
AU - Hodges, P.
AU - Gurfinkel, V.
AU - Brumagne, S.
AU - Smith, T.
AU - Cordo, P.
PY - 2002/6/15
Y1 - 2002/6/15
N2 - This study evaluated the extent to which movement of the lower limbs and pelvis may compensate for the disturbance to posture that results from respiratory movement of the thorax and abdomen. Motion of the neck, pelvis, leg and centre of pressure (COP) were recorded with high resolution in conjunction with electromyographic activity (EMG) of flexor and extensor muscles of the trunk and hip. Respiration was measured from ribcage motion. Subjects breathed quietly, and with increased volume due to hypercapnoea (as a result of breathing with increased dead-space) and a voluntary increase in respiration. Additional recordings were made during apnoea. The relationship between respiration and other parameters was measured from the correlation between data in the frequency domain (i.e. coherence) and from time-locked averages triggered from respiration. In quiet standing, small angular displacements (∼0.5°) of the trunk and leg were identified in raw data. Correspondingly, there were peaks in the power spectra of the angular movements and EMG. While body movement and EMG were coherent with respiration (>0.5), the coherence between respiration and COP displacement was low (<0.2). The amplitude of movement and coherence was increased when respiration was increased. The present data suggest that the postural disturbance that results from respiratory movement is matched, at least partly, and counteracted by small angular displacements of the lower trunk and lower limbs. Thus, stability in quiet stance is dependent on movement of multiple body segments and control of equilibrium cannot be reduced to control of a single joint.
AB - This study evaluated the extent to which movement of the lower limbs and pelvis may compensate for the disturbance to posture that results from respiratory movement of the thorax and abdomen. Motion of the neck, pelvis, leg and centre of pressure (COP) were recorded with high resolution in conjunction with electromyographic activity (EMG) of flexor and extensor muscles of the trunk and hip. Respiration was measured from ribcage motion. Subjects breathed quietly, and with increased volume due to hypercapnoea (as a result of breathing with increased dead-space) and a voluntary increase in respiration. Additional recordings were made during apnoea. The relationship between respiration and other parameters was measured from the correlation between data in the frequency domain (i.e. coherence) and from time-locked averages triggered from respiration. In quiet standing, small angular displacements (∼0.5°) of the trunk and leg were identified in raw data. Correspondingly, there were peaks in the power spectra of the angular movements and EMG. While body movement and EMG were coherent with respiration (>0.5), the coherence between respiration and COP displacement was low (<0.2). The amplitude of movement and coherence was increased when respiration was increased. The present data suggest that the postural disturbance that results from respiratory movement is matched, at least partly, and counteracted by small angular displacements of the lower trunk and lower limbs. Thus, stability in quiet stance is dependent on movement of multiple body segments and control of equilibrium cannot be reduced to control of a single joint.
KW - Frequency analysis
KW - Kinematics
KW - Postural control
KW - Respiration
KW - Stability
UR - http://www.scopus.com/inward/record.url?scp=0036268759&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036268759&partnerID=8YFLogxK
U2 - 10.1007/s00221-002-1040-x
DO - 10.1007/s00221-002-1040-x
M3 - Article
C2 - 12021811
AN - SCOPUS:0036268759
VL - 144
SP - 293
EP - 302
JO - Experimental Brain Research
JF - Experimental Brain Research
SN - 0014-4819
IS - 3
ER -