Why Both One-Leg Stand Times May Matter
In 3,278 independent older adults in Japan, a shorter time on the weaker side was associated with later loss of independence or death, even when the better side reached 30 seconds.
The 60-second version
The shorter of two one-leg stand times was associated with severe loss of independence or death over follow-up in independently living older Japanese adults.
Key points
- The cohort included 3,278 adults aged 65 or older and recorded 452 composite events over a median 7.22 years.
- Compared with at least 30 seconds, adjusted hazard ratios were 2.17 below 10 seconds and 1.54 from 10 to 20 seconds.
- The shorter side remained informative even when the better side reached at least 30 seconds.
- The observational design, composite endpoint and two-community sample prevent causal or universal conclusions.
Verdict. Measuring both sides may improve low-cost risk assessment, but the result belongs inside a broader clinical evaluation and does not predict an individual's fate.
Among 3,278 independent Japanese adults aged 65 or older, the shorter result from bilateral one-leg standing tests was associated with later severe loss of independence or death. The signal remained even when the better-performing leg reached 30 seconds.
DesignA bilateral test followed over seven years
| Population | 3,278 independently living adults aged 65 or older in two Japanese municipalities. |
|---|---|
| Exposure | The secondary one-leg stand time: the shorter result from the two sides. |
| Follow-up | Median 7.22 years after testing between 2008 and 2010. |
| Outcome | Death or severe loss of independence requiring complete help with basic daily activities. |
ResultsRisk rose below twenty seconds
| Under 10 seconds | Adjusted hazard ratio 2.17; 95% CI 1.67 to 2.84, compared with at least 30 seconds. |
|---|---|
| 10 to 20 seconds | Adjusted hazard ratio 1.54; 95% CI 1.13 to 2.10. |
| 20 to 30 seconds | Adjusted hazard ratio 0.88; 95% CI 0.56 to 1.37, with no clear increase. |
| Better side at least 30 seconds | The shorter side still carried an association in the restricted analysis. |
Hazard ratios compare event rates over time after adjustment; they are not probabilities. The reference was a shorter-side time of at least 30 seconds. Confidence intervals show that the 20-to-30-second estimate remained compatible with both lower and higher risk.
MeaningA screening signal, not a single-number verdict
- 1. Confounding: balance can reflect neurological, musculoskeletal, visual, medication and general-health factors.
- 2. Composite outcome: severe dependency and death are distinct events and should not be collapsed into a mortality claim.
- 3. Generalizability: the cohort began with independent older adults in two Japanese communities.
- 4. Safety: people at fall risk should not attempt unsupervised threshold testing.
Testing only the better leg may discard useful information, but testing both legs does not turn balance into destiny.
PracticeUse both sides within a broader assessment
Bilateral testing could complement gait speed, strength, fall history, cognition, vision, medication review and daily function. A short result should lead to clinical context and safer evaluation, not self-diagnosis.
The authors declared no conflicts of interest. Intervention studies are still needed to learn whether acting on the weaker-side result changes severe dependency or survival.
Primary sourcesTelegram post 1509·JAMDA paper·PubMed record·Crossref record·OpenAlex record