ÍáÍáÂþ»­

ROCHESTER, Minn. — There are a host of elevated metrics out there for the signaling of poor health.

They include and among others.

Now we can add a low number to this list of tests. It's the ability to stand for less than 10 seconds on one leg.

The test is taken barefoot, with your free foot tucked behind the calf of your standing leg, arms at your sides.

It's called your One Legged Stance performance. adults between 50 and 75 who could not do this for 10 seconds faced twice the risk of early death over those who could.

To repeat, this was a balance test that predicted mortality. Not your ability to play hopscotch, join the circus or make the Olympics. It predicted your elevated risk of earlier death.

Researchers believe it's part of a whole new way of looking at certain skills of physical function that we might otherwise regard as peripheral to the numbers that matter.

"Any marker of functional status, however you measure it, is going to (mean) less mortality," said Dr. Michael Joyner, a Mayo Clinic clinician and expert on human performance who was not involved in the study. "Even if you have chronic disease, if you have high physical function, you're going to be somewhat protected from death."

"In my view, stability should be the fourth component of fitness, as you can be very aerobically fit, very flexible, and very strong, but not very stable," Dr. Edward R. Laskowski said in an email.

A specialist in physical medicine and rehabilitation and sports medicine at Mayo Clinic, Laskowski describes stability as "the sensory system transferring information from the ground and from our muscles and joints as we move," one which can become impaired after common injuries.

The Brazilian study assessed the skill between 2008 and 2020, following the health outcomes for 1,700 men and women aged 51-75 tested for balance while attending a sports medicine clinic in Rio de Janeiro. It did not track for falls, but it excluded those with balance disorders. The researchers gave participants three tries to get it right.

The good news is that only a fifth of those studied failed the test, that those who died in the near future were an even smaller subset of the whole, and that failing the test was in no way a death sentence. The researchers found that just 20 % of those tested failed, and only 7.2% of all participants died in the following ten years.

But of those who died during the period of study, 4.6% had passed the test, while 17.6% had failed. After controlling for other variables of longevity, that translated to a 1.84 hazard ratio, or nearly twice the risk of death.

The authors did not say what bodily survival system was identified by the red blinking light of a failed OLS test, and could not rule out falls as a mechanism leading to early death. But they believed it could be considered a unique marker of all-cause mortality to be added to routine physical examinations.

"This study showed that people who could stand on one foot lived longer," said Joyner, who says similar findings can be demonstrated by studies showing "that people who couldn't get off the floor died much faster than people who could get off the floor. You can demonstrate this with grip strength. You can demonstrate it with push-ups."

In 2013, that the ability to sit to the floor in a controlled descent, then rise all without the use of hands, predicted risk of all cause mortality. By 2015, identified grip strength as a more important predictor of cardiovascular disease risk than systolic blood pressure.

Then, by 2019, researchers had that the ability to complete more than 40 push-ups was associated with a significantly reduced risk of heart disease compared to those who could do less than 10.

"Basically any group of people, middle aged or older," Joyner said, "where you see physical strength or physical frailty, you're going to see some sort of relationship like this."

"Simple exercises such as standing on one leg when we're brushing our teeth, when performed repeatedly, train and improve our system of stability," Laskowski said. He also recommends tai chi. "The more we challenge our stability system, the better at stability we will become."

"What's important is how little exercise and training is required for people to not be frail," Joyner said. "By not sitting around, by being physically active and doing things, people are not going to get frail ... The main thing is to do something."