IADMS New York 2002   [back to the Category]

Effect of Training on Postural Control and Center of Pressure Displacement During Weight Shift   [read the french version]

Author :   Sheyi Ojofeitimi, MPT & Al.

Effect of Training on Postural Control and Center of
Pressure Displacement During Weight Shift


Sheyi Ojofeitimi, MPT; Shaw Bronner, PT, MHS, OCS;
Jonathan Spriggs, BEng; Bruce Brownstein, PT
SOAR Research, Long Island University
Brooklyn, New York, USA

Purpose: The objective of this work is to examine the effect of training on lower limb sequence, center of pressure (CP) displacement, and identify movement strategies during weight shift followed by a unilateral balance. Understanding the effects of dance training on postural strategies of young adults will facilitate improvements in rehabilitative methods for balance related problems other populations.

Methods: Seventeen expert dancers and 17 non-dancers (20 females and 14 males, age 20-40) volunteered for this study. 3-D kinematic data of a reaction time weight shift sequence were collected at 120 Hz with a five camera motion analysis system. Force, moment and CP data were collected at 1,080 Hz while standing on a force plate. Analyses included reaction time and joint movement sequencing of the ankle, hip, and pelvis. Latency of CP displacement and coefficient of variability during the hold phase were used to determine postural control differences between groups. Independent t-tests were performed to assess between group differences.

Results: There was no significant difference in reaction times or joint movement sequence between groups. Lateral CP displacement towards the gesture limb occurred in both groups. Duration and amplitude of CP displacement was significantly different between groups. Movement onset of the gesture limb occurs before the end of body weight transfer in both groups. Coefficient of variability of the gesture limb and CP during the hold phase was lower in dancers. Analysis of the frequency response during this phase corroborates this observation. Differences between displacements of the support limb acromion and trochanter markers revealed dancers maintained more vertical trunk alignment during the weight shift task.

Conclusion: Dancers maintained better control of their CP and gesture limb during unilateral balance. Initial shift of CP towards the gesture limb, and use of translation and inclination strategies in dancers and novices respectively confirm the findings of Mouchnino et al. (1992).

Reference: Mouchinino R, Aurenty R, Massion J, Pedotti A (1992). Coordination between equilibrium and head-trunk orientation during leg movement: A new strategy built up by training. J Neurophysiol 67:1587-98.

Acknowledgments: Supported in part by the Fan Fox and Leslie R. Samuels Foundation and NIH MBRS Grant # SO6 GM54650-04.