Under 60, small-sample sit-to-stand references exist: about 6 s in the 20s and 30s, 7.6 s in the 40s
What is a normal 5 times sit-to-stand time under 60?
The finding
Mean times (± SD): 6.0 ± 1.4 s at 20–29, 6.1 ± 1.4 at 30–39, 7.6 ± 1.8 at 40–49 and 7.7 ± 2.6 at 50–59.
- Authors
- Bohannon RW, Bubela DJ, Magasi SR, Wang YC, Gershon RC
- Published
- Isokinetics and Exercise Science 18(4):235–40 · 2010
- Evidence
- Read in the primary source; numbers checked.
- Source
- doi.org/10.3233/IES-2010-0389
How it was studied
181 community-dwelling NIH Toolbox enrollees aged 14–85 (111 women, 70 men). 43 cm armless chair, arms folded, timed from "go" to sitting after the fifth stand; best of two trials.
The numbers
Older groups: 7.8 ± 2.4 s at 60–69, 9.3 ± 2.1 at 70–79 and 10.8 ± 2.6 at 80–85, which is 3–4 s faster than the 2006 meta-analysis. Knee-extension strength explained the most variance; sex added nothing once strength was in the model.
What it does not show
15–36 people per decade, healthy volunteers. The disagreement with the 2006 meta-analysis means the choice of reference changes a percentile a lot.
What Longstanding does with it
Under 60 the app scores sit-to-stand against these means and SDs, with the spread assumed normal, and labels the reference a small sample. Because the 2006 table it uses from 60 is 3–4 s slower, the same time ranks higher from 60, and the backcast line holds its age-60 value before 60.