The Effects of Changing Base of Support on Balance Strategies
This study examines the effects of altering the base of support on balance strategies. There have been many studies that have attempted to identify strategies that individuals use to control posture. The ankle strategy is used to maintain balance by rotating at the ankle joint for smaller perturbations, while the hip strategy is adopted when the ankle muscles can no longer control balance. Rotating at the hip joint maintains posture during larger perturbations. Unfortunately there is not much research on how changing the base of support will affect balance control without perturbation. The present study examines the center of pressure displacement of 8 college age (18-24 years) subjects (4female, 4male) as the support surface becomes smaller in length. The subjects were asked to stand on a force platform in a quiet stance for 10 trials with 5 different surface lengths. As the subjects attempt to maintain balance for 30 seconds, center of pressure (COP) data is drawn from the force platform underneath the supports surface and analyzed. A video camera is also used to examine the postural sways that occur during balance stabilization. After studying balance control concepts it can be hypothesized that the ankle is the normal strategy adopted during quiet stance for healthy adults. As the surface length decreases individuals will shift from an ankle to a hip strategy. The decreased support surface will result in an increase in COP amplitude and velocity. This experiment should provide evidence of the connection between the COP displacement and balance strategies with respect to the size of the base of support.
School:
University of Illinois at Urbana-Champaign
Department:
N/A
Research Advisor:
Karl Rosengren
Department of Research Advisor:
Kinesiology
Year of Publication:
2002