Objective: The aim of the study was to investigate the age-related ability of dynamic balance recovery through perturbation response during standing.Method: Six older and 6 younger adults participated in this study. External perturbation during standing as pulling force applied at the pelvic level in the anterior direction was provided to the subject. The margin of stability was quantified as a measure of postural stability or dynamic balance recovery, and using principal component analysis (PCA), the regularity of the margin of stability (MoS) was calculated.Results: Our results showed that in the older adult group, 60.99% and 28.63% of the total variance were captured using the first and second principal components (PCs), respectively, and in the younger adult group, 81.95% and 10.71% of the total variance were captured using the first and second PCs, respectively.Conclusion: Ninety percent of the total variance captured using the first two PCs indicates that the older adults had decreased regularity of the MoS than the younger adults. Thus, the results of the present study suggest that aging is associated with non-regularity of dynamic postural stability.

The elderly accounted for 13.1% of the entire population of Korea in 2015, with 6,624,000 individuals, and are projected to account for 40% of the total population in 2060. The drastic increase in medical expenses for the elderly (3,220,000 Won per person in 2014) is becoming a social problem (StatisticsKorea, 2015). From a social welfare point of view, the idea of disseminating various types of exercise equipment to reduce medical expenses for the elderly is spreading (Josephs, Pratt, Meadows, Thurmond, & Wagner, 2016).Exercise training programs for the elderly have evolved in different ways. Korean exercise training programs such as Pilates (Kim, Rhyu, &