Sit-to-stand movement score and locomo-age to detect locomotive syndrome in older adults

Abstract

\n Background Aging is characterized by biological changes, such as reductions in muscle strength and the loss of mobility and balance. The Japanese Orthopaedic Association proposed the term “locomotive syndrome” (LS) to define people at risk of requiring nursing care because of problems with locomotive system. A need exists to develop simple methods to quantify motor performance and allow the early detection of LS. Sit-to-stand (STS) movements are a mechanically demanding daily task and represent motor performance. Using the Nintendo Wii Balance Board (WBB), we have developed a novel method to quantify STS movements—the “STS score.” This study investigated differences in the STS score across LS severity in healthy older adults. To recognize motor performance easily, we then defined the “locomo-age” to represent the individual’s age based on the LS status.Methods We investigated whether the STS score can predict LS. This study enrolled 152 participants of 65 years and above. Participants were divided into three groups based on LS risk test results. Participants were instructed to stand up as quickly as possible on the WBB, and the STS score was calculated based on the combination of the speed and balance indices. We also evaluated motor status by calculating the peak power during STS and performing a timed up and go test and handgrip strength test. To calculate locomo-age, we used a regression equation between STS scores and age from a data set in our previous study.Results The LS stage was increased significantly with age, whereas the association with body mass index was not significant. The STS score and timed up and go results were good indicators to detect LS. However, neither peak power nor handgrip strength could significantly distinguish between the LS stages.Conclusions Measurement of the LS is important to assess older adults’ motor performance. The novel STS score is an easy-to-use method that requires limited space and only one person to operate. The STS score decreased significantly with the LS severity and thus could be used to assess LS in older adults. The locomo-age of the STS score is useful to understand the LS status.