Relative sit‐to‐stand power: aging trajectories, functionally relevant cut‐off points, and normative data in a large European cohort

Background A validated, standardized, and feasible test to assess muscle power in older adults has recently been reported: the sit-to-stand (STS) test. This investigation aimed relationship between relative STS age provide normative data, cut-off points, minimal clinically important differences (MCID) for measures women men. Methods total of 9320 (6161 3159 men) aged 60–103 years 586 young middle-aged (318 268 20–60 were included this cross-sectional study. Relative (normalized body mass), allometric height squared), specific legs mass) values assessed by 30 s Body composition was evaluated dual energy X-ray absorptiometry bioelectrical impedance analysis, skeletal index (SMI; normalized squared) calculated. Habitual maximal gait speed, timed up-and-go test, 6 min walking distance collected as physical performance measures, participants classified into two groups: well-functioning mobility-limited adults. Results found decrease 30–50 (−0.05 W·kg−1·year−1; P > 0.05), 50–80 (−0.10 −0.13 < 0.001), above 80 (−0.07 −0.08 0.001). 1129 (18%) 510 men (16%) presented mobility limitations. Mobility-limited exhibited lower relative, allometric, power; higher mass (BMI) SMI (both only women); (only than their counterparts (all 0.05). Normative data points BMI reported. Low occurred below 2.1 W·kg−1 (area under curve, AUC, [95% confidence interval, CI] = 0.85 [0.84–0.87]) 2.6 (AUC 0.89 [0.87–0.91]). The age-adjusted odds ratios limitations with low 10.6 [9.0–12.6] 14.1 [10.9–18.2], respectively. MCID 0.33 0.42 Conclusions decreased significantly after 50 negatively strongly associated Our study provides functionally relevant use daily clinical practice.