The test
The ten-second balance test
One leg, eyes open, ten seconds. It needs nothing, takes ten seconds, and carries more outcome evidence behind it than any other single measurement in the Evolution Index.
What you need. Nothing. Stand next to a counter or wall you can grab.
How to do it
Doing it properly
- Stand on one leg, other foot off the floor and not resting against your standing leg.
- Arms by your sides. Eyes open, looking straight ahead.
- Time until you put the other foot down, grab support, or reach 30 seconds.
What stops the clock
The clock stops the moment your raised foot touches anything, you take hold of the support, or you reach 30 seconds. One attempt, not the best of three.
What most people get wrong
- Resting the raised foot against the standing calf.
- Hopping.
- Looking at the floor.
The evidence
What it actually shows
Araujo and colleagues measured 1,702 adults aged 51 to 75 and followed them for a median of seven years. Those who could not hold a ten-second one-legged stand died at 1.84 times the rate of those who could, after adjusting for age, sex, body mass and existing illness.
That figure is why the Evolution Index treats this as a floor rather than a score. Fail the ten seconds and the whole Index is held down, however well the other eight tests go. Balance is not a bonus, and a domain cannot be averaged away by the two beside it.
For how long you can hold it, rather than whether you reach ten seconds, the reference is the English Longitudinal Study of Ageing: 7,658 adults, nationally representative, weighted percentiles by age and sex.
Nobody under 51 was in the Araujo study. Below that age the ten-second test says very little either way — holding it at forty is expected rather than informative.
It is an observational finding. It shows that poor balance and earlier death travel together; it does not show that one causes the other, and no study has shown that training your balance extends anyone's life.
Eyes open, the test hits a ceiling in midlife. Sixty-nine per cent of 53-year-olds hold the full thirty seconds, so above about fifty it stops separating people. That is why the Index also records the eyes-closed version, where the median at 53 is five seconds.
The ELSA percentiles cover ages 50 to 69 and nothing outside that, because the study only administered the test to that range. They also carry no mortality or falls data at all: a percentile here is where you stand, not a prediction about you.
Araujo CG and colleagues. British Journal of Sports Medicine, 2022. 1,702 adults aged 51–75, median follow-up seven years.
Grgic J, Wazny VK, Kirk B, Poon ETC, Valenzuela PL. Reference values for gait speed, five-times-sit-to-stand test, balance, and handgrip strength. GeroScience 2026. ELSA wave 6, n=7,658, ages 50–69.
The next step
One test is one test.
This measures one thing. The Evolution Index measures nine, across the three domains that decide how long you stay useful, and reports your weakest rather than your average — a strong heart does not buy you out of a floor you cannot get up from.
Every score is published with the error around it, because a change smaller than the measurement error is not a change.