Evolution Index
Matt Roberts EvolutionA quick test — try it now
Can you stand on one leg for ten seconds?
Ten seconds, no equipment, and the strongest single predictor of anything measured here. It is one of the ten measurements in the Evolution Index — the quickest, and the one you can do before you finish reading this.
Shoes off if you can. Eyes open, hands wherever you like, the raised foot clear of the standing leg. Steady yourself on something for the first second, then let go.
Start the clock, then lift one foot. If you put it down before the end, stop the clock — an honest ten seconds is the whole point of the measurement.
Why ten seconds
One balance test, seven years of follow-up.
Adults who could not hold a ten-second one-legged stand died at a higher rate over the following years than adults who could — after the numbers were adjusted for age, sex, body mass and existing illness.
Nobody under 51 was in the study, so for anyone younger the test says very little either way. Holding ten seconds 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 training your balance has not been shown to extend anyone's life.
It is also one test. It says nothing about how hard your heart can work, how much force you can produce, or whether you can get off the floor unaided.
Araujo CG and colleagues, British Journal of Sports Medicine, 2022. The same threshold is used as a floor inside the Evolution Index, for the reason above: balance is not a bonus.
The measurement
Nine tests. One number. Error bars published.
The balance test is one of nine. Together they measure the three things that decide how long you stay useful, and your score on each is your percentile — where you stand against adults your age and sex.
Biological age guesses at what your body is. This measures what it can do.
Your weakest domain sets your band, not 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.
Fifty is average, and average means declining at the same rate as everyone else your age. That is ageing on schedule rather than holding your ground, so Holding starts at 55: you have to beat typical to reach it.
Which has a consequence worth saying out loud rather than leaving you to find on your own result. Scoring 50 puts you in Slipping, and roughly six in ten people land in Slipping or Reversing. That is what the population data shows. It is not a fault in the scale.
You also get a Capacity Age: the age at which your measurements would be holding their ground rather than declining. Most people read an age faster than a percentile. Where your result runs past the ages the reference data actually covers, it says so — “30 or younger” — rather than inventing a number.
What the number is for
The score is the diagnosis. The programme is the point.
If movement is the domain holding your Index down, no amount of cardio moves it. Most people train what they are already good at, because that is the part that feels like progress.
Twelve weeks, built around the domain holding your Index down. Retested at the end on the same tests, so you can see what moved and by how much.
The retest is included. It is the reason the price holds: a twelve-week plan that cannot tell you whether it worked is a guess with a schedule attached.
The practice
Measured in Mayfair, on calibrated equipment.
The test is free and you run it yourself. The assessed Index is measured by the Evolution team, and the two are not the same thing — a self-measured result carries the wider error of self-measurement, and says so on the page.