Which sit-to-stand test best differentiates functional capacity in older people?

Abstract

The Sit-to-Stand (STS) test provides insight into age-related functional capacity; however, there are various variants of STS, and we do not know which of these better discriminates against age-related functional capacity. Our study aimed to compare the age-related functional capacity in older people by evaluating STS power variants, using young individuals as a reference. A cross-sectional study was conducted in 102 adults (57 women) aged 60-80 and 105 adults (54 women) aged 20-30. Participants performed five times STS (5-STS), 30-seconds STS (30s-STS), and 1-minute STS (1min-STS). Z-scores were obtained for each STS variant using power (W), relative (W/kg), and allometric (W/m2) normalization methods. A mixed repeated-measures ANOVA assessed the interactions among the STS variants, normalization methods, sex, physical activity, and tobacco history. A significant interaction between STS variants, normalization methods, and sex (p=0.002) was found. The mean effect of STS variants revealed that the 1-minSTS had the lowest Z-score (p<0.05). Significant variations were observed between STS variants in all normalization methods for women (p<0.001). However, in men, only the difference between 5-STS and 1min-STS remained consistent across normalization methods (p<0.05). Our findings highlight the efficacy of 1min-STS in distinguishing age-related functional capacity over the other STS tests, especially in women.