Physical Aspects of Healthy Aging: Assessments of Three Measures of Balance for Studies in Middle-Aged and Older Adults

Table 1

Balance platform main variables (×4 tests).

Variable name	Description
Mediolateral (ML) sway	Distance which contains 90% of lateral displacement of center of forces
Anterior-posterior (AP) sway	Distance which contains 90% of anterior-posterior displacement of center of forces
Length of side of square	Length of the smallest square containing 90% of path of center of forces
Mean X speed	Average speed of lateral movement of center of forces
Mean Y speed	Average speed of anteroposterior movement of center of forces
Velocity moment	Average horizontal area covered by movement of center of forces per second
Correlation	Correlation between lateral and antero-posterior movement of center of forces
Direction of main axis	Angle of direction of average movement of center of forces
	Right = 0 degrees
	Forward = 90 degrees
	Left = 180 degrees
	Backward = 270 degrees
Mean X value	Average value of center point on lateral axis (left is negative)
Mean Y value	Center point on anterior-posterior axis—leaning to the front/back