Many of us played "golden rooster" as children — hopping onto one leg and trying to knock each other over. It felt like nothing more than a game. But researchers have found that the same childish move, performed seriously, is a surprisingly strong window into how well you are aging.
The Test: How Long Can You Stand on One Leg?
A Japanese research team, in a study published in the Journal of the American Medical Directors Association (J Am Med Dir Assoc, 2025), analyzed data from the Aizu Cohort Study (LOHAS) of community-dwelling older adults. Their finding: if the weaker side of your one-leg standing lasts less than 10 seconds, your risk of losing independence or dying is 2.17 times higher than someone who can stand on one leg for 30 seconds or more.
The association also followed a clear dose–response pattern: every 10 seconds shorter in one-leg standing time raised the combined risk of "loss of independence or death" by 42%. The team grouped participants by their "secondary" (weaker) side — standing times of ≥30, 20–30, 10–20, and <10 seconds — and adjusted for age, sex, BMI, and multiple chronic conditions to isolate the net effect. A similar negative dose–response relationship held for all-cause mortality alone.
Even a "Strong" Leg Can't Mask a Weak One
Most of us have a preferred leg — the one that stands longer (the dominant side) and one that gives out sooner (the secondary side). You might think: if my good leg can hold 30 seconds, my balance must be fine, right? The researchers anticipated that too, and ran a subgroup analysis on participants whose dominant leg could stand for 30 seconds or more.
The result was blunt: if the other leg still fell short of 30 seconds, the combined risk of disability or death went up anyway. They also regrouped participants into those who could stand 30 seconds on both legs, those who could only manage it on one leg, and those who failed on both. Only "both legs pass" came with the lowest risk. A strong dominant side does not cancel out a weak secondary side.
Why Does Balance Predict Health?
One-leg standing looks simple, but it is a demanding feat of coordination. It requires muscle strength, nerve conduction, vestibular (inner-ear) sensing, proprioception, and joint mobility to work together as a single system. That is why standing time is not just about "leg power" — it is a readout of how well many body systems are cooperating.
Because so many systems are involved, early signs of trouble can surface here first: early neurodegenerative disease, silent cerebrovascular changes, or latent sarcopenia
