Reference Values for Five-Repetition Chair Stand Test Among Middle-Aged and Elderly Community-Dwelling Chinese Adults

Background: Previous studies on the five-repetition chair stand test (CS-5) are limited by the representativeness of the sample or the lack of reference equations for CS-5. Defined reference values for CS-5 in a large population are not available for middle-aged and elderly Chinese adults. Objective: We established age- and sex-stratified reference values for CS-5 times in a large population in China, and to investigate the associations between demographic and anthropometric factors and CS-5 times. Methods: Analysis of data from the national baseline survey of the China Health and Retirement Longitudinal Study, a nationally representative longitudinal survey that includes 450 urban communities and rural villages within 28 provinces, municipalities, and autonomous regions of China. Results: Twelve thousand six hundred five of seventeen thousand seven hundred eight participants were included for the reference value analyses. Twelve thousand three hundred out of seventeen thousand seven hundred eight participants were included for the risk factor analyses. Of 12,605 participants, the mean CS-5 time was 10.13 s (SD, 3.32) in men and 11.03 s (SD, 3.54) in women aged 40+ year. The CS-5 times were shorter in men than women of all age categories (P < 0.001). The cut-off points ranged from 5.36 to 9.98 s and from 6.48 to 10.29 s in men and women, respectively. Mean velocity was higher in men than in women (P < 0.001). Age, waist circumference, living in a rural village, and having chronic diseases were positively associated with CS-5 time, whereas male, handgrip strength, currently married, income, and current or ex-drinker were negatively associated with CS-5 time in this population (all P < 0.001). Conclusions: The comprehensive normative values for CS-5 are essential for enabling clinicians to better evaluate functional performance, determine the appropriate interventional strategy, and promote healthy aging of older adults.